How to use EvaluateExpressionAsync method of PuppeteerSharp.ExecutionContext class

Best Puppeteer-sharp code snippet using PuppeteerSharp.ExecutionContext.EvaluateExpressionAsync

PageEvaluateTests.cs

Source:PageEvaluateTests.cs

...135        [PuppeteerFact]136        public async Task ShouldSupportThrownStringsAsErrorMessages()137        {138            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(139                () => Page.EvaluateExpressionAsync("throw 'qwerty'"));140            Assert.Contains("qwerty", exception.Message);141        }142        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should support thrown numbers as error messages")]143        [PuppeteerFact]144        public async Task ShouldSupportThrownNumbersAsErrorMessages()145        {146            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(147                            () => Page.EvaluateExpressionAsync("throw 100500"));148            Assert.Contains("100500", exception.Message);149        }150        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should return complex objects")]151        [PuppeteerFact]152        public async Task SouldReturnComplexObjects()153        {154            dynamic obj = new155            {156                foo = "bar!"157            };158            var result = await Page.EvaluateFunctionAsync("a => a", obj);159            Assert.Equal("bar!", result.foo.ToString());160        }161        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should return BigInt")]162        [PuppeteerFact]163        public async Task ShouldReturnBigInt()164        {165            var result = await Page.EvaluateFunctionAsync<object>("() => BigInt(42)");166            Assert.Equal(new BigInteger(42), result);167        }168        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should return NaN")]169        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should return -0")]170        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should return Infinity")]171        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should return -Infinity")]172        [Theory]173        [InlineData("() => NaN", double.NaN)] //ShouldReturnNaN174        [InlineData("() => -0", -0)] //ShouldReturnNegative0175        [InlineData("() => Infinity", double.PositiveInfinity)] //ShouldReturnInfinity176        [InlineData("() => -Infinity", double.NegativeInfinity)] //ShouldReturnNegativeInfinty177        public async Task BasicEvaluationTest(string script, object expected)178        {179            var result = await Page.EvaluateFunctionAsync<object>(script);180            Assert.Equal(expected, result);181        }182        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should accept \"undefined\" as one of multiple parameters")]183        [PuppeteerFact]184        public async Task ShouldAcceptNullAsOneOfMultipleParameters()185        {186            var result = await Page.EvaluateFunctionAsync<bool>(187                "(a, b) => Object.is(a, null) && Object.is(b, 'foo')",188                null,189                "foo");190            Assert.True(result);191        }192        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should return undefined for non-serializable objects")]193        [SkipBrowserFact(skipFirefox: true)]194        public async Task ShouldReturnNullForNonSerializableObjects()195            => Assert.Null(await Page.EvaluateFunctionAsync("() => window"));196        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should fail for circular object")]197        [SkipBrowserFact(skipFirefox: true)]198        public async Task ShouldFailForCircularObject()199        {200            var result = await Page.EvaluateFunctionAsync(@"() => {201                const a = {};202                const b = {a};203                a.b = b;204                return a;205            }");206            Assert.Null(result);207        }208        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should be able to throw a tricky error")]209        [SkipBrowserFact(skipFirefox: true)]210        public async Task ShouldBeAbleToThrowATrickyError()211        {212            var windowHandle = await Page.EvaluateFunctionHandleAsync("() => window");213            PuppeteerException exception = await Assert.ThrowsAsync<MessageException>(() => windowHandle.JsonValueAsync());214            var errorText = exception.Message;215            exception = await Assert.ThrowsAsync<EvaluationFailedException>(() => Page.EvaluateFunctionAsync(@"errorText =>216            {217                throw new Error(errorText);218            }", errorText));219            Assert.Contains(errorText, exception.Message);220        }221        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should accept a string")]222        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should accept a string with semi colons")]223        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should accept a string with comments")]224        [Theory]225        [InlineData("1 + 2;", 3)]226        [InlineData("1 + 5;", 6)]227        [InlineData("2 + 5\n// do some math!'", 7)]228        public async Task BasicIntExressionEvaluationTest(string script, object expected)229        {230            var result = await Page.EvaluateExpressionAsync<int>(script);231            Assert.Equal(expected, result);232        }233        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should accept element handle as an argument")]234        [PuppeteerFact]235        public async Task ShouldAcceptElementHandleAsAnArgument()236        {237            await Page.SetContentAsync("<section>42</section>");238            var element = await Page.QuerySelectorAsync("section");239            var text = await Page.EvaluateFunctionAsync<string>("e => e.textContent", element);240            Assert.Equal("42", text);241        }242        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should throw if underlying element was disposed")]243        [PuppeteerFact]244        public async Task ShouldThrowIfUnderlyingElementWasDisposed()245        {246            await Page.SetContentAsync("<section>39</section>");247            var element = await Page.QuerySelectorAsync("section");248            Assert.NotNull(element);249            await element.DisposeAsync();250            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(()251                => Page.EvaluateFunctionAsync<string>("e => e.textContent", element));252            Assert.Contains("JSHandle is disposed", exception.Message);253        }254        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should throw if elementHandles are from other frames")]255        [SkipBrowserFact(skipFirefox: true)]256        public async Task ShouldThrowIfElementHandlesAreFromOtherFrames()257        {258            await FrameUtils.AttachFrameAsync(Page, "frame1", TestConstants.EmptyPage);259            var bodyHandle = await Page.FirstChildFrame().QuerySelectorAsync("body");260            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(()261                => Page.EvaluateFunctionAsync<string>("body => body.innerHTML", bodyHandle));262            Assert.Contains("JSHandles can be evaluated only in the context they were created", exception.Message);263        }264        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should simulate a user gesture")]265        [SkipBrowserFact(skipFirefox: true)]266        public async Task ShouldSimulateAUserGesture()267            => Assert.True(await Page.EvaluateFunctionAsync<bool>(@"() => {268                document.body.appendChild(document.createTextNode('test'));269                document.execCommand('selectAll');270                return document.execCommand('copy');271            }"));272        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should throw a nice error after a navigation")]273        [SkipBrowserFact(skipFirefox: true)]274        public async Task ShouldThrowANiceErrorAfterANavigation()275        {276            var executionContext = await Page.MainFrame.GetExecutionContextAsync();277            await Task.WhenAll(278                Page.WaitForNavigationAsync(),279                executionContext.EvaluateFunctionAsync("() => window.location.reload()")280            );281            var ex = await Assert.ThrowsAsync<EvaluationFailedException>(() =>282            {283                return executionContext.EvaluateFunctionAsync("() => null");284            });285            Assert.Contains("navigation", ex.Message);286        }287        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should not throw an error when evaluation does a navigation")]288        [SkipBrowserFact(skipFirefox: true)]289        public async Task ShouldNotThrowAnErrorWhenEvaluationDoesANavigation()290        {291            await Page.GoToAsync(TestConstants.ServerUrl + "/one-style.html");292            var result = await Page.EvaluateFunctionAsync<int[]>(@"() =>293            {294                window.location = '/empty.html';295                return [42];296            }");297            Assert.Equal(new[] { 42 }, result);298        }299        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should transfer 100Mb of data from page to node.js")]300        [PuppeteerFact]301        public async Task ShouldTransfer100MbOfDataFromPage()302        {303            var a = await Page.EvaluateFunctionAsync<string>("() => Array(100 * 1024 * 1024 + 1).join('a')");304            Assert.Equal(100 * 1024 * 1024, a.Length);305        }306        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should throw error with detailed information on exception inside promise ")]307        [PuppeteerFact]308        public async Task ShouldThrowErrorWithDetailedInformationOnExceptionInsidePromise()309        {310            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(() =>311                Page.EvaluateFunctionAsync(312                    @"() => new Promise(() => {313                        throw new Error('Error in promise');314                    })"));315            Assert.Contains("Error in promise", exception.Message);316        }317        [PuppeteerFact]318        public async Task ShouldWorkWithDifferentSerializerSettings()319        {320            var result = await Page.EvaluateFunctionAsync<ComplexObjectTestClass>("() => { return { foo: 'bar' }}");321            Assert.Equal("bar", result.Foo);322            result = (await Page.EvaluateFunctionAsync<JToken>("() => { return { Foo: 'bar' }}"))323                .ToObject<ComplexObjectTestClass>(new JsonSerializerSettings());324            Assert.Equal("bar", result.Foo);325            result = await Page.EvaluateExpressionAsync<ComplexObjectTestClass>("var obj = { foo: 'bar' }; obj;");326            Assert.Equal("bar", result.Foo);327            result = (await Page.EvaluateExpressionAsync<JToken>("var obj = { Foo: 'bar' }; obj;"))328                .ToObject<ComplexObjectTestClass>(new JsonSerializerSettings());329            Assert.Equal("bar", result.Foo);330        }331        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should properly serialize null fields")]332        [PuppeteerFact]333        public async Task ShouldProperlySerializeNullFields()334        {335            var result = await Page.EvaluateFunctionAsync<Dictionary<string, object>>("() => ({a: null})");336            Assert.True(result.ContainsKey("a"));337            Assert.Null(result["a"]);338        }339        [PuppeteerTest("evaluation.spec.ts", "Page.evaluate", "should accept element handle as an argument")]340        [PuppeteerFact]341        public async Task ShouldAcceptObjectHandleAsAnArgument()342        {343            await Page.SetContentAsync("<section>42</section>");344            var element = await Page.QuerySelectorAsync("section");345            var text = await Page.EvaluateFunctionAsync<string>("(e) => e.textContent", element);346            Assert.Equal("42", text);347        }348        [PuppeteerFact]349        public async Task ShouldWorkWithoutGenerics()350        {351            Assert.NotNull(await Page.EvaluateExpressionAsync("var obj = {}; obj;"));352            Assert.NotNull(await Page.EvaluateExpressionAsync("[]"));353            Assert.NotNull(await Page.EvaluateExpressionAsync("''"));354            var objectPopulated = await Page.EvaluateExpressionAsync("var obj = {a:1}; obj;");355            Assert.NotNull(objectPopulated);356            Assert.Equal(1, objectPopulated["a"]);357            var arrayPopulated = await Page.EvaluateExpressionAsync("[1]");358            Assert.IsType<JArray>(arrayPopulated);359            Assert.Equal(1, ((JArray)arrayPopulated)[0]);360            Assert.Equal("1", await Page.EvaluateExpressionAsync("'1'"));361            Assert.Equal(1, await Page.EvaluateExpressionAsync("1"));362            Assert.Equal(11111111, await Page.EvaluateExpressionAsync("11111111"));363            Assert.Equal(11111111111111, await Page.EvaluateExpressionAsync("11111111111111"));364            Assert.Equal(1.1, await Page.EvaluateExpressionAsync("1.1"));365        }366        public class ComplexObjectTestClass367        {368            public string Foo { get; set; }369        }370    }371}...

EvaluateTests.cs

Source:EvaluateTests.cs

...115        [Fact]116        public async Task ShouldSupportThrownStringsAsErrorMessages()117        {118            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(119                () => Page.EvaluateExpressionAsync("throw 'qwerty'"));120            Assert.Contains("qwerty", exception.Message);121        }122        [Fact]123        public async Task ShouldSupportThrownNumbersAsErrorMessages()124        {125            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(126                            () => Page.EvaluateExpressionAsync("throw 100500"));127            Assert.Contains("100500", exception.Message);128        }129        [Fact]130        public async Task SouldReturnComplexObjects()131        {132            dynamic obj = new133            {134                foo = "bar!"135            };136            var result = await Page.EvaluateFunctionAsync("a => a", obj);137            Assert.Equal("bar!", result.foo.ToString());138        }139        [Fact]140        public async Task ShouldReturnBigInt()141        {142            var result = await Page.EvaluateFunctionAsync<object>("() => BigInt(42)");143            Assert.Equal(new BigInteger(42), result);144        }145        [Theory]146        [InlineData("() => NaN", double.NaN)] //ShouldReturnNaN147        [InlineData("() => -0", -0)] //ShouldReturnNegative0148        [InlineData("() => Infinity", double.PositiveInfinity)] //ShouldReturnInfinity149        [InlineData("() => -Infinity", double.NegativeInfinity)] //ShouldReturnNegativeInfinty150        public async Task BasicEvaluationTest(string script, object expected)151        {152            var result = await Page.EvaluateFunctionAsync<object>(script);153            Assert.Equal(expected, result);154        }155        [Fact]156        public async Task ShouldAcceptNullAsOneOfMultipleParameters()157        {158            var result = await Page.EvaluateFunctionAsync<bool>(159                "(a, b) => Object.is(a, null) && Object.is(b, 'foo')",160                null,161                "foo");162            Assert.True(result);163        }164        [Fact]165        public async Task ShouldReturnNullForNonSerializableObjects()166            => Assert.Null(await Page.EvaluateFunctionAsync("() => window"));167        [Fact]168        public async Task ShouldFailForCircularObject()169        {170            var result = await Page.EvaluateFunctionAsync(@"() => {171                const a = {};172                const b = {a};173                a.b = b;174                return a;175            }");176            Assert.Null(result);177        }178        [Fact]179        public async Task ShouldBeAbleToThrowATrickyError()180        {181            var windowHandle = await Page.EvaluateFunctionHandleAsync("() => window");182            PuppeteerException exception = await Assert.ThrowsAsync<MessageException>(() => windowHandle.JsonValueAsync());183            var errorText = exception.Message;184            exception = await Assert.ThrowsAsync<EvaluationFailedException>(() => Page.EvaluateFunctionAsync(@"errorText =>185            {186                throw new Error(errorText);187            }", errorText));188            Assert.Contains(errorText, exception.Message);189        }190        [Theory]191        [InlineData("1 + 5;", 6)] //ShouldAcceptSemiColons192        [InlineData("2 + 5\n// do some math!'", 7)] //ShouldAceptStringComments193        public async Task BasicIntExressionEvaluationTest(string script, object expected)194        {195            var result = await Page.EvaluateExpressionAsync<int>(script);196            Assert.Equal(expected, result);197        }198        [Fact]199        public async Task ShouldAcceptElementHandleAsAnArgument()200        {201            await Page.SetContentAsync("<section>42</section>");202            var element = await Page.QuerySelectorAsync("section");203            var text = await Page.EvaluateFunctionAsync<string>("e => e.textContent", element);204            Assert.Equal("42", text);205        }206        [Fact]207        public async Task ShouldThrowIfUnderlyingElementWasDisposed()208        {209            await Page.SetContentAsync("<section>39</section>");210            var element = await Page.QuerySelectorAsync("section");211            Assert.NotNull(element);212            await element.DisposeAsync();213            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(()214                => Page.EvaluateFunctionAsync<string>("e => e.textContent", element));215            Assert.Contains("JSHandle is disposed", exception.Message);216        }217        [Fact]218        public async Task ShouldThrowIfElementHandlesAreFromOtherFrames()219        {220            await FrameUtils.AttachFrameAsync(Page, "frame1", TestConstants.EmptyPage);221            var bodyHandle = await Page.FirstChildFrame().QuerySelectorAsync("body");222            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(()223                => Page.EvaluateFunctionAsync<string>("body => body.innerHTML", bodyHandle));224            Assert.Contains("JSHandles can be evaluated only in the context they were created", exception.Message);225        }226        [Fact]227        public async Task ShouldSimulateAUserGesture()228            => Assert.True(await Page.EvaluateFunctionAsync<bool>(@"() => {229                document.body.appendChild(document.createTextNode('test'));230                document.execCommand('selectAll');231                return document.execCommand('copy'); 232            }"));233        [Fact]234        public async Task ShouldThrowANiceErrorAfterANavigation()235        {236            var executionContext = await Page.MainFrame.GetExecutionContextAsync();237            await Task.WhenAll(238                Page.WaitForNavigationAsync(),239                executionContext.EvaluateFunctionAsync("() => window.location.reload()")240            );241            var ex = await Assert.ThrowsAsync<EvaluationFailedException>(() =>242            {243                return executionContext.EvaluateFunctionAsync("() => null");244            });245            Assert.Contains("navigation", ex.Message);246        }247        [Fact]248        public async Task ShouldNotThrowAnErrorWhenEvaluationDoesANavigation()249        {250            await Page.GoToAsync(TestConstants.ServerUrl + "/one-style.html");251            var result = await Page.EvaluateFunctionAsync<int[]>(@"() =>252            {253                window.location = '/empty.html';254                return [42];255            }");256            Assert.Equal(new[] { 42 }, result);257        }258        /// <summary>259        /// Original Name "should transfer 100Mb of data from page to node.js"260        /// </summary>261        [Fact]262        public async Task ShouldTransfer100MbOfDataFromPage()263        {264            var a = await Page.EvaluateFunctionAsync<string>("() => Array(100 * 1024 * 1024 + 1).join('a')");265            Assert.Equal(100 * 1024 * 1024, a.Length);266        }267        [Fact]268        public async Task ShouldThrowErrorWithDetailedInformationOnExceptionInsidePromise()269        {270            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(() =>271                Page.EvaluateFunctionAsync(272                    @"() => new Promise(() => {273                        throw new Error('Error in promise');274                    })"));275            Assert.Contains("Error in promise", exception.Message);276        }277        [Fact]278        public async Task ShouldWorkWithDifferentSerializerSettings()279        {280            var result = await Page.EvaluateFunctionAsync<ComplexObjectTestClass>("() => { return { foo: 'bar' }}");281            Assert.Equal("bar", result.Foo);282            result = (await Page.EvaluateFunctionAsync<JToken>("() => { return { Foo: 'bar' }}"))283                .ToObject<ComplexObjectTestClass>(new JsonSerializerSettings());284            Assert.Equal("bar", result.Foo);285            result = await Page.EvaluateExpressionAsync<ComplexObjectTestClass>("var obj = { foo: 'bar' }; obj;");286            Assert.Equal("bar", result.Foo);287            result = (await Page.EvaluateExpressionAsync<JToken>("var obj = { Foo: 'bar' }; obj;"))288                .ToObject<ComplexObjectTestClass>(new JsonSerializerSettings());289            Assert.Equal("bar", result.Foo);290        }291        [Fact]292        public async Task ShouldProperlyIgnoreUndefinedFields()293        {294            var result = await Page.EvaluateFunctionAsync<Dictionary<string, object>>("() => ({a: undefined})");295            Assert.Empty(result);296        }297        [Fact]298        public async Task ShouldProperlySerializeNullFields()299        {300            var result = await Page.EvaluateFunctionAsync<Dictionary<string, object>>("() => ({a: null})");301            Assert.True(result.ContainsKey("a"));302            Assert.Null(result["a"]);303        }304        [Fact]305        public async Task ShouldAcceptObjectHandleAsAnArgument()306        {307            var navigatorHandle = await Page.EvaluateExpressionHandleAsync("navigator");308            var text = await Page.EvaluateFunctionAsync<string>("e => e.userAgent", navigatorHandle);309            Assert.Contains("Mozilla", text);310        }311        [Fact]312        public async Task ShouldAcceptObjectHandleToPrimitiveTypes()313        {314            var aHandle = await Page.EvaluateExpressionHandleAsync("5");315            var isFive = await Page.EvaluateFunctionAsync<bool>("e => Object.is(e, 5)", aHandle);316            Assert.True(isFive);317        }318        [Fact]319        public async Task ShouldWarnOnNestedObjectHandles()320        {321            var handle = await Page.EvaluateFunctionHandleAsync("() => document.body");322            var elementHandle = handle as ElementHandle;323            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(()324                => Page.EvaluateFunctionHandleAsync(325                    "opts => opts.elem.querySelector('p')",326                    new { elem = handle }));327            Assert.Contains("Are you passing a nested JSHandle?", exception.Message);328            //Check with ElementHandle329            exception = await Assert.ThrowsAsync<EvaluationFailedException>(()330                => Page.EvaluateFunctionHandleAsync(331                    "opts => opts.elem.querySelector('p')",332                    new { elem = elementHandle }));333            Assert.Contains("Are you passing a nested JSHandle?", exception.Message);334        }335        [Fact]336        public async Task ShouldWorkWithoutGenerics()337        {338            Assert.NotNull(await Page.EvaluateExpressionAsync("var obj = {}; obj;"));339            Assert.NotNull(await Page.EvaluateExpressionAsync("[]"));340            Assert.NotNull(await Page.EvaluateExpressionAsync("''"));341            var objectPopulated = await Page.EvaluateExpressionAsync("var obj = {a:1}; obj;");342            Assert.NotNull(objectPopulated);343            Assert.Equal(1, objectPopulated["a"]);344            var arrayPopulated = await Page.EvaluateExpressionAsync("[1]");345            Assert.IsType<JArray>(arrayPopulated);346            Assert.Equal(1, ((JArray)arrayPopulated)[0]);347            Assert.Equal("1", await Page.EvaluateExpressionAsync("'1'"));348            Assert.Equal(1, await Page.EvaluateExpressionAsync("1"));349            Assert.Equal(11111111, await Page.EvaluateExpressionAsync("11111111"));350            Assert.Equal(11111111111111, await Page.EvaluateExpressionAsync("11111111111111"));351            Assert.Equal(1.1, await Page.EvaluateExpressionAsync("1.1"));352        }353        public class ComplexObjectTestClass354        {355            public string Foo { get; set; }356        }357    }358}...

DOMWorld.cs

Source:DOMWorld.cs

...65        {66            var context = await GetExecutionContextAsync().ConfigureAwait(false);67            return await context.EvaluateFunctionHandleAsync(script, args).ConfigureAwait(false);68        }69        internal async Task<T> EvaluateExpressionAsync<T>(string script)70        {71            var context = await GetExecutionContextAsync().ConfigureAwait(false);72            return await context.EvaluateExpressionAsync<T>(script).ConfigureAwait(false);73        }74        internal async Task<JToken> EvaluateExpressionAsync(string script)75        {76            var context = await GetExecutionContextAsync().ConfigureAwait(false);77            return await context.EvaluateExpressionAsync(script).ConfigureAwait(false);78        }79        internal async Task<T> EvaluateFunctionAsync<T>(string script, params object[] args)80        {81            var context = await GetExecutionContextAsync().ConfigureAwait(false);82            return await context.EvaluateFunctionAsync<T>(script, args).ConfigureAwait(false);83        }84        internal async Task<JToken> EvaluateFunctionAsync(string script, params object[] args)85        {86            var context = await GetExecutionContextAsync().ConfigureAwait(false);87            return await context.EvaluateFunctionAsync(script, args).ConfigureAwait(false);88        }89        internal Task<string> GetContentAsync() => EvaluateFunctionAsync<string>(@"() => {90                let retVal = '';91                if (document.doctype)92                    retVal = new XMLSerializer().serializeToString(document.doctype);93                if (document.documentElement)94                    retVal += document.documentElement.outerHTML;95                return retVal;96            }");97        internal async Task SetContentAsync(string html, NavigationOptions options = null)98        {99            var waitUntil = options?.WaitUntil ?? new[] { WaitUntilNavigation.Load };100            var timeout = options?.Timeout ?? _timeoutSettings.NavigationTimeout;101            // We rely upon the fact that document.open() will reset frame lifecycle with "init"102            // lifecycle event. @see https://crrev.com/608658103            await EvaluateFunctionAsync(@"html => {104                document.open();105                document.write(html);106                document.close();107            }", html).ConfigureAwait(false);108            using (var watcher = new LifecycleWatcher(_frameManager, Frame, waitUntil, timeout))109            {110                var watcherTask = await Task.WhenAny(111                    watcher.TimeoutOrTerminationTask,112                    watcher.LifecycleTask).ConfigureAwait(false);113                await watcherTask.ConfigureAwait(false);114            }115        }116        internal async Task<ElementHandle> AddScriptTagAsync(AddTagOptions options)117        {118            const string addScriptUrl = @"async function addScriptUrl(url, type) {119              const script = document.createElement('script');120              script.src = url;121              if(type)122                script.type = type;123              const promise = new Promise((res, rej) => {124                script.onload = res;125                script.onerror = rej;126              });127              document.head.appendChild(script);128              await promise;129              return script;130            }";131            const string addScriptContent = @"function addScriptContent(content, type = 'text/javascript') {132              const script = document.createElement('script');133              script.type = type;134              script.text = content;135              let error = null;136              script.onerror = e => error = e;137              document.head.appendChild(script);138              if (error)139                throw error;140              return script;141            }";142            async Task<ElementHandle> AddScriptTagPrivate(string script, string urlOrContent, string type)143            {144                var context = await GetExecutionContextAsync().ConfigureAwait(false);145                return (string.IsNullOrEmpty(type)146                        ? await context.EvaluateFunctionHandleAsync(script, urlOrContent).ConfigureAwait(false)147                        : await context.EvaluateFunctionHandleAsync(script, urlOrContent, type).ConfigureAwait(false)) as ElementHandle;148            }149            if (!string.IsNullOrEmpty(options.Url))150            {151                var url = options.Url;152                try153                {154                    return await AddScriptTagPrivate(addScriptUrl, url, options.Type).ConfigureAwait(false);155                }156                catch (PuppeteerException)157                {158                    throw new PuppeteerException($"Loading script from {url} failed");159                }160            }161            if (!string.IsNullOrEmpty(options.Path))162            {163                var contents = await AsyncFileHelper.ReadAllText(options.Path).ConfigureAwait(false);164                contents += "//# sourceURL=" + options.Path.Replace("\n", string.Empty);165                return await AddScriptTagPrivate(addScriptContent, contents, options.Type).ConfigureAwait(false);166            }167            if (!string.IsNullOrEmpty(options.Content))168            {169                return await AddScriptTagPrivate(addScriptContent, options.Content, options.Type).ConfigureAwait(false);170            }171            throw new ArgumentException("Provide options with a `Url`, `Path` or `Content` property");172        }173        internal async Task<ElementHandle> AddStyleTagAsync(AddTagOptions options)174        {175            const string addStyleUrl = @"async function addStyleUrl(url) {176              const link = document.createElement('link');177              link.rel = 'stylesheet';178              link.href = url;179              const promise = new Promise((res, rej) => {180                link.onload = res;181                link.onerror = rej;182              });183              document.head.appendChild(link);184              await promise;185              return link;186            }";187            const string addStyleContent = @"async function addStyleContent(content) {188              const style = document.createElement('style');189              style.type = 'text/css';190              style.appendChild(document.createTextNode(content));191              const promise = new Promise((res, rej) => {192                style.onload = res;193                style.onerror = rej;194              });195              document.head.appendChild(style);196              await promise;197              return style;198            }";199            if (!string.IsNullOrEmpty(options.Url))200            {201                var url = options.Url;202                try203                {204                    var context = await GetExecutionContextAsync().ConfigureAwait(false);205                    return (await context.EvaluateFunctionHandleAsync(addStyleUrl, url).ConfigureAwait(false)) as ElementHandle;206                }207                catch (PuppeteerException)208                {209                    throw new PuppeteerException($"Loading style from {url} failed");210                }211            }212            if (!string.IsNullOrEmpty(options.Path))213            {214                var contents = await AsyncFileHelper.ReadAllText(options.Path).ConfigureAwait(false);215                contents += "//# sourceURL=" + options.Path.Replace("\n", string.Empty);216                var context = await GetExecutionContextAsync().ConfigureAwait(false);217                return (await context.EvaluateFunctionHandleAsync(addStyleContent, contents).ConfigureAwait(false)) as ElementHandle;218            }219            if (!string.IsNullOrEmpty(options.Content))220            {221                var context = await GetExecutionContextAsync().ConfigureAwait(false);222                return (await context.EvaluateFunctionHandleAsync(addStyleContent, options.Content).ConfigureAwait(false)) as ElementHandle;223            }224            throw new ArgumentException("Provide options with a `Url`, `Path` or `Content` property");225        }226        internal Task<ElementHandle> WaitForSelectorAsync(string selector, WaitForSelectorOptions options = null)227            => WaitForSelectorOrXPathAsync(selector, false, options);228        internal Task<ElementHandle> WaitForXPathAsync(string xpath, WaitForSelectorOptions options = null)229            => WaitForSelectorOrXPathAsync(xpath, true, options);230        internal Task<JSHandle> WaitForFunctionAsync(string script, WaitForFunctionOptions options, params object[] args)231            => new WaitTask(232                this,233                script,234                false,235                "function",236                options.Polling,237                options.PollingInterval,238                options.Timeout ?? _timeoutSettings.Timeout,239                args).Task;240        internal Task<JSHandle> WaitForExpressionAsync(string script, WaitForFunctionOptions options)241            => new WaitTask(242                this,243                script,244                true,245                "function",246                options.Polling,247                options.PollingInterval,248                options.Timeout ?? _timeoutSettings.Timeout).Task;249        internal Task<string> GetTitleAsync() => EvaluateExpressionAsync<string>("document.title");250        private async Task<ElementHandle> GetDocument()251        {252            if (_documentCompletionSource == null)253            {254                _documentCompletionSource = new TaskCompletionSource<ElementHandle>(TaskCreationOptions.RunContinuationsAsynchronously);255                var context = await GetExecutionContextAsync().ConfigureAwait(false);256                var document = await context.EvaluateExpressionHandleAsync("document").ConfigureAwait(false);257                _documentCompletionSource.TrySetResult(document as ElementHandle);258            }259            return await _documentCompletionSource.Task.ConfigureAwait(false);260        }261        private async Task<ElementHandle> WaitForSelectorOrXPathAsync(string selectorOrXPath, bool isXPath, WaitForSelectorOptions options = null)262        {263            options = options ?? new WaitForSelectorOptions();...

FrameWaitForSelectorTests.cs

Source:FrameWaitForSelectorTests.cs

...26        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should work with removed MutationObserver")]27        [SkipBrowserFact(skipFirefox: true)]28        public async Task ShouldWorkWithRemovedMutationObserver()29        {30            await Page.EvaluateExpressionAsync("delete window.MutationObserver");31            var waitForSelector = Page.WaitForSelectorAsync(".zombo");32            await Task.WhenAll(33                waitForSelector,34                Page.SetContentAsync("<div class='zombo'>anything</div>"));35            Assert.Equal("anything", await Page.EvaluateFunctionAsync<string>("x => x.textContent", await waitForSelector));36        }37        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should resolve promise when node is added")]38        [PuppeteerFact]39        public async Task ShouldResolveTaskWhenNodeIsAdded()40        {41            await Page.GoToAsync(TestConstants.EmptyPage);42            var frame = Page.MainFrame;43            var watchdog = frame.WaitForSelectorAsync("div");44            await frame.EvaluateFunctionAsync(AddElement, "br");45            await frame.EvaluateFunctionAsync(AddElement, "div");46            var eHandle = await watchdog;47            var property = await eHandle.GetPropertyAsync("tagName");48            var tagName = await property.JsonValueAsync<string>();49            Assert.Equal("DIV", tagName);50        }51        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should work when node is added through innerHTML")]52        [PuppeteerFact]53        public async Task ShouldWorkWhenNodeIsAddedThroughInnerHTML()54        {55            await Page.GoToAsync(TestConstants.EmptyPage);56            var watchdog = Page.WaitForSelectorAsync("h3 div");57            await Page.EvaluateFunctionAsync(AddElement, "span");58            await Page.EvaluateExpressionAsync("document.querySelector('span').innerHTML = '<h3><div></div></h3>'");59            await watchdog;60        }61        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "Page.waitForSelector is shortcut for main frame")]62        [PuppeteerFact]63        public async Task PageWaitForSelectorAsyncIsShortcutForMainFrame()64        {65            await Page.GoToAsync(TestConstants.EmptyPage);66            await FrameUtils.AttachFrameAsync(Page, "frame1", TestConstants.EmptyPage);67            var otherFrame = Page.FirstChildFrame();68            var watchdog = Page.WaitForSelectorAsync("div");69            await otherFrame.EvaluateFunctionAsync(AddElement, "div");70            await Page.EvaluateFunctionAsync(AddElement, "div");71            var eHandle = await watchdog;72            Assert.Equal(Page.MainFrame, eHandle.ExecutionContext.Frame);73        }74        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should run in specified frame")]75        [PuppeteerFact]76        public async Task ShouldRunInSpecifiedFrame()77        {78            await FrameUtils.AttachFrameAsync(Page, "frame1", TestConstants.EmptyPage);79            await FrameUtils.AttachFrameAsync(Page, "frame2", TestConstants.EmptyPage);80            var frame1 = Page.FirstChildFrame();81            var frame2 = Page.Frames.ElementAt(2);82            var waitForSelectorPromise = frame2.WaitForSelectorAsync("div");83            await frame1.EvaluateFunctionAsync(AddElement, "div");84            await frame2.EvaluateFunctionAsync(AddElement, "div");85            var eHandle = await waitForSelectorPromise;86            Assert.Equal(frame2, eHandle.ExecutionContext.Frame);87        }88        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should throw when frame is detached")]89        [SkipBrowserFact(skipFirefox: true)]90        public async Task ShouldThrowWhenFrameIsDetached()91        {92            await FrameUtils.AttachFrameAsync(Page, "frame1", TestConstants.EmptyPage);93            var frame = Page.FirstChildFrame();94            var waitTask = frame.WaitForSelectorAsync(".box").ContinueWith(task => task?.Exception?.InnerException);95            await FrameUtils.DetachFrameAsync(Page, "frame1");96            var waitException = await waitTask;97            Assert.NotNull(waitException);98            Assert.Contains("waitForFunction failed: frame got detached.", waitException.Message);99        }100        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should survive cross-process navigation")]101        [PuppeteerFact]102        public async Task ShouldSurviveCrossProcessNavigation()103        {104            var boxFound = false;105            var waitForSelector = Page.WaitForSelectorAsync(".box").ContinueWith(_ => boxFound = true);106            await Page.GoToAsync(TestConstants.EmptyPage);107            Assert.False(boxFound);108            await Page.ReloadAsync();109            Assert.False(boxFound);110            await Page.GoToAsync(TestConstants.CrossProcessHttpPrefix + "/grid.html");111            await waitForSelector;112            Assert.True(boxFound);113        }114        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should wait for visible")]115        [PuppeteerFact]116        public async Task ShouldWaitForVisible()117        {118            var divFound = false;119            var waitForSelector = Page.WaitForSelectorAsync("div", new WaitForSelectorOptions { Visible = true })120                .ContinueWith(_ => divFound = true);121            await Page.SetContentAsync("<div style='display: none; visibility: hidden;'>1</div>");122            Assert.False(divFound);123            await Page.EvaluateExpressionAsync("document.querySelector('div').style.removeProperty('display')");124            Assert.False(divFound);125            await Page.EvaluateExpressionAsync("document.querySelector('div').style.removeProperty('visibility')");126            Assert.True(await waitForSelector);127            Assert.True(divFound);128        }129        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should wait for visible recursively")]130        [PuppeteerFact]131        public async Task ShouldWaitForVisibleRecursively()132        {133            var divVisible = false;134            var waitForSelector = Page.WaitForSelectorAsync("div#inner", new WaitForSelectorOptions { Visible = true })135                .ContinueWith(_ => divVisible = true);136            await Page.SetContentAsync("<div style='display: none; visibility: hidden;'><div id='inner'>hi</div></div>");137            Assert.False(divVisible);138            await Page.EvaluateExpressionAsync("document.querySelector('div').style.removeProperty('display')");139            Assert.False(divVisible);140            await Page.EvaluateExpressionAsync("document.querySelector('div').style.removeProperty('visibility')");141            Assert.True(await waitForSelector);142            Assert.True(divVisible);143        }144        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "hidden should wait for visibility: hidden")]145        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "hidden should wait for display: none")]146        [Theory]147        [InlineData("visibility", "hidden")]148        [InlineData("display", "none")]149        public async Task HiddenShouldWaitForVisibility(string propertyName, string propertyValue)150        {151            var divHidden = false;152            await Page.SetContentAsync("<div style='display: block;'></div>");153            var waitForSelector = Page.WaitForSelectorAsync("div", new WaitForSelectorOptions { Hidden = true })154                .ContinueWith(_ => divHidden = true);155            await Page.WaitForSelectorAsync("div"); // do a round trip156            Assert.False(divHidden);157            await Page.EvaluateExpressionAsync($"document.querySelector('div').style.setProperty('{propertyName}', '{propertyValue}')");158            Assert.True(await waitForSelector);159            Assert.True(divHidden);160        }161        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "hidden should wait for removal")]162        [PuppeteerFact]163        public async Task HiddenShouldWaitForRemoval()164        {165            await Page.SetContentAsync("<div></div>");166            var divRemoved = false;167            var waitForSelector = Page.WaitForSelectorAsync("div", new WaitForSelectorOptions { Hidden = true })168                .ContinueWith(_ => divRemoved = true);169            await Page.WaitForSelectorAsync("div"); // do a round trip170            Assert.False(divRemoved);171            await Page.EvaluateExpressionAsync("document.querySelector('div').remove()");172            Assert.True(await waitForSelector);173            Assert.True(divRemoved);174        }175        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should return null if waiting to hide non-existing element")]176        [PuppeteerFact]177        public async Task ShouldReturnNullIfWaitingToHideNonExistingElement()178        {179            var handle = await Page.WaitForSelectorAsync("non-existing", new WaitForSelectorOptions { Hidden = true });180            Assert.Null(handle);181        }182        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should respect timeout")]183        [PuppeteerFact]184        public async Task ShouldRespectTimeout()185        {186            var exception = await Assert.ThrowsAsync<WaitTaskTimeoutException>(async ()187                => await Page.WaitForSelectorAsync("div", new WaitForSelectorOptions { Timeout = 10 }));188            Assert.Contains("waiting for selector 'div' failed: timeout", exception.Message);189        }190        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should have an error message specifically for awaiting an element to be hidden")]191        [PuppeteerFact]192        public async Task ShouldHaveAnErrorMessageSpecificallyForAwaitingAnElementToBeHidden()193        {194            await Page.SetContentAsync("<div></div>");195            var exception = await Assert.ThrowsAsync<WaitTaskTimeoutException>(async ()196                => await Page.WaitForSelectorAsync("div", new WaitForSelectorOptions { Hidden = true, Timeout = 10 }));197            Assert.Contains("waiting for selector 'div' to be hidden failed: timeout", exception.Message);198        }199        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should respond to node attribute mutation")]200        [PuppeteerFact]201        public async Task ShouldRespondToNodeAttributeMutation()202        {203            var divFound = false;204            var waitForSelector = Page.WaitForSelectorAsync(".zombo").ContinueWith(_ => divFound = true);205            await Page.SetContentAsync("<div class='notZombo'></div>");206            Assert.False(divFound);207            await Page.EvaluateExpressionAsync("document.querySelector('div').className = 'zombo'");208            Assert.True(await waitForSelector);209        }210        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should return the element handle")]211        [PuppeteerFact]212        public async Task ShouldReturnTheElementHandle()213        {214            var waitForSelector = Page.WaitForSelectorAsync(".zombo");215            await Page.SetContentAsync("<div class='zombo'>anything</div>");216            Assert.Equal("anything", await Page.EvaluateFunctionAsync<string>("x => x.textContent", await waitForSelector));217        }218        [PuppeteerTest("waittask.spec.ts", "Frame.waitForSelector", "should have correct stack trace for timeout")]219        [PuppeteerFact]220        public async Task ShouldHaveCorrectStackTraceForTimeout()221        {...

ExecutionContext.cs

Source:ExecutionContext.cs

...46        /// </remarks>47        /// <seealso cref="EvaluateFunctionAsync{T}(string, object[])"/>48        /// <seealso cref="EvaluateExpressionHandleAsync(string)"/>49        /// <returns>Task which resolves to script return value</returns>50        public Task<JToken> EvaluateExpressionAsync(string script) => EvaluateExpressionAsync<JToken>(script);51        /// <summary>52        /// Executes a script in browser context53        /// </summary>54        /// <typeparam name="T">The type to deserialize the result to</typeparam>55        /// <param name="script">Script to be evaluated in browser context</param>56        /// <remarks>57        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.58        /// </remarks>59        /// <seealso cref="EvaluateFunctionAsync{T}(string, object[])"/>60        /// <seealso cref="EvaluateExpressionHandleAsync(string)"/>61        /// <returns>Task which resolves to script return value</returns>62        public Task<T> EvaluateExpressionAsync<T>(string script)63            => RemoteObjectTaskToObject<T>(EvaluateExpressionInternalAsync(true, script));64        internal async Task<JSHandle> EvaluateExpressionHandleAsync(string script)65            => CreateJSHandle(await EvaluateExpressionInternalAsync(false, script).ConfigureAwait(false));66        /// <summary>67        /// Executes a function in browser context68        /// </summary>69        /// <param name="script">Script to be evaluated in browser context</param>70        /// <param name="args">Arguments to pass to script</param>71        /// <remarks>72        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.73        /// <see cref="JSHandle"/> instances can be passed as arguments74        /// </remarks>75        /// <seealso cref="EvaluateExpressionAsync{T}(string)"/>76        /// <returns>Task which resolves to script return value</returns>77        public Task<JToken> EvaluateFunctionAsync(string script, params object[] args) => EvaluateFunctionAsync<JToken>(script, args);78        /// <summary>79        /// Executes a function in browser context80        /// </summary>81        /// <typeparam name="T">The type to deserialize the result to</typeparam>82        /// <param name="script">Script to be evaluated in browser context</param>83        /// <param name="args">Arguments to pass to script</param>84        /// <remarks>85        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.86        /// <see cref="JSHandle"/> instances can be passed as arguments87        /// </remarks>88        /// <seealso cref="EvaluateExpressionAsync{T}(string)"/>89        /// <returns>Task which resolves to script return value</returns>90        public Task<T> EvaluateFunctionAsync<T>(string script, params object[] args)91            => RemoteObjectTaskToObject<T>(EvaluateFunctionInternalAsync(true, script, args));92        internal async Task<JSHandle> EvaluateFunctionHandleAsync(string script, params object[] args)93            => CreateJSHandle(await EvaluateFunctionInternalAsync(false, script, args).ConfigureAwait(false));94        /// <summary>95        /// The method iterates JavaScript heap and finds all the objects with the given prototype.96        /// </summary>97        /// <returns>A task which resolves to a handle to an array of objects with this prototype.</returns>98        /// <param name="prototypeHandle">A handle to the object prototype.</param>99        public async Task<JSHandle> QueryObjectsAsync(JSHandle prototypeHandle)100        {101            if (prototypeHandle.Disposed)102            {...

Worker.cs

Source:Worker.cs

...71        /// <param name="script">Script to be evaluated in browser context</param>72        /// <remarks>73        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.74        /// </remarks>75        /// <seealso cref="ExecutionContext.EvaluateExpressionAsync(string)"/>76        /// <returns>Task which resolves to script return value</returns>77        public async Task<T> EvaluateExpressionAsync<T>(string script)78            => await (await ExecutionContextTask.ConfigureAwait(false)).EvaluateExpressionAsync<T>(script).ConfigureAwait(false);79        /// <summary>80        /// Executes a script in browser context81        /// </summary>82        /// <param name="script">Script to be evaluated in browser context</param>83        /// <remarks>84        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.85        /// </remarks>86        /// <returns>Task which resolves to script return value</returns>87        /// <seealso cref="ExecutionContext.EvaluateExpressionHandleAsync(string)"/>88        public async Task<JSHandle> EvaluateExpressionHandleAsync(string script)89            => await (await ExecutionContextTask.ConfigureAwait(false)).EvaluateExpressionHandleAsync(script).ConfigureAwait(false);90        internal Task<ExecutionContext> ExecutionContextTask => _executionContextCallback.Task;91        internal async void OnMessageReceived(object sender, MessageEventArgs e)92        {...

QueryObjectsTests.cs

Source:QueryObjectsTests.cs

...15        [SkipBrowserFact(skipFirefox: true)]16        public async Task ShouldWork()17        {18            // Instantiate an object19            await Page.EvaluateExpressionAsync("window.set = new Set(['hello', 'world'])");20            var prototypeHandle = await Page.EvaluateExpressionHandleAsync("Set.prototype");21            var objectsHandle = await Page.QueryObjectsAsync(prototypeHandle);22            var count = await Page.EvaluateFunctionAsync<int>("objects => objects.length", objectsHandle);23            Assert.Equal(1, count);24            var values = await Page.EvaluateFunctionAsync<string[]>("objects => Array.from(objects[0].values())", objectsHandle);25            Assert.Equal(new[] { "hello", "world" }, values);26        }27        [PuppeteerTest("page.spec.ts", "ExecutionContext.queryObjects", "should work for non-blank page")]28        [SkipBrowserFact(skipFirefox: true)]29        public async Task ShouldWorkForNonBlankPage()30        {31            // Instantiate an object32            await Page.GoToAsync(TestConstants.EmptyPage);33            await Page.EvaluateFunctionAsync("() => window.set = new Set(['hello', 'world'])");...

ExecutionContextTests.cs

Source:ExecutionContextTests.cs

...25            Assert.NotEqual(context1, context2);26            Assert.Equal(Page.MainFrame, context1.Frame);27            Assert.Equal(Page.FirstChildFrame(), context2.Frame);28            await Task.WhenAll(29                context1.EvaluateExpressionAsync("window.a = 1"),30                context2.EvaluateExpressionAsync("window.a = 2")31            );32            var a1 = context1.EvaluateExpressionAsync<int>("window.a");33            var a2 = context2.EvaluateExpressionAsync<int>("window.a");34            await Task.WhenAll(a1, a2);35            Assert.Equal(1, a1.Result);36            Assert.Equal(2, a2.Result);37        }38    }39}

EvaluateExpressionAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);9            var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = false });10            var page = await browser.NewPageAsync();11            await page.WaitForSelectorAsync("input[name='q']");12            await page.EvaluateExpressionAsync("document.querySelector('input[name=\"q\"]').value='puppeteer'");13            await page.ClickAsync("input[name='btnK']");14            await page.WaitForNavigationAsync();15            Console.WriteLine("Done");16            Console.ReadLine();17            await browser.CloseAsync();18        }19    }20}21using System;22using System.Threading.Tasks;23using PuppeteerSharp;24{25    {26        static async Task Main(string[] args)27        {28            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);29            var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = false });30            var page = await browser.NewPageAsync();

EvaluateExpressionAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);9            var browser = await Puppeteer.LaunchAsync(new LaunchOptions10            {11            });12            var page = await browser.NewPageAsync();13            var result = await page.EvaluateExpressionAsync<string>("document.title");14            Console.WriteLine(result);15            await browser.CloseAsync();16        }17    }18}19using System;20using System.Threading.Tasks;21using PuppeteerSharp;22{23    {24        static async Task Main(string[] args)25        {26            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);27            var browser = await Puppeteer.LaunchAsync(new LaunchOptions28            {29            });30            var page = await browser.NewPageAsync();31            var result = await page.EvaluateExpressionAsync<int>("1+1");32            Console.WriteLine(result);33            await browser.CloseAsync();34        }35    }36}37using System;38using System.Threading.Tasks;39using PuppeteerSharp;40{41    {42        static async Task Main(string[] args)43        {44            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);45            var browser = await Puppeteer.LaunchAsync(new LaunchOptions46            {47            });48            var page = await browser.NewPageAsync();49            var result = await page.EvaluateExpressionAsync<int>("document.querySelectorAll('a').length");50            Console.WriteLine(result);51            await browser.CloseAsync();52        }53    }54}

EvaluateExpressionAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            var browser = await Puppeteer.LaunchAsync(new LaunchOptions9            {10            });11            var page = await browser.NewPageAsync();12            var element = await page.QuerySelectorAsync("input[name='q']");13            await element.TypeAsync("Puppeteer");14            var result = await page.EvaluateExpressionAsync("document.querySelector('input[name=\"q\"]').value");15            Console.WriteLine(resul

EvaluateExpressionAsync

Using AI Code Generation

1var page = await browser.NewPageAsync();2var expression = "document.querySelector('div').innerText";3var result = await page.MainFrame.EvaluateExpressionAsync<string>(expression);4Console.WriteLine(result);5var page = await browser.NewPageAsync();6var expression = "document.querySelector('div').innerText";7var result = await page.MainFrame.EvaluateExpressionAsync<string>(expression);8Console.WriteLine(result);9var page = await browser.NewPageAsync();10var expression = "document.querySelector('div').innerText";11var result = await page.MainFrame.EvaluateExpressionAsync<string>(expression);12Console.WriteLine(result);13var page = await browser.NewPageAsync();14var expression = "document.querySelector('div').innerText";15var result = await page.MainFrame.EvaluateExpressionAsync<string>(expression);16Console.WriteLine(result);17var page = await browser.NewPageAsync();18var expression = "document.querySelector('div').innerText";19var result = await page.MainFrame.EvaluateExpressionAsync<string>(expression);20Console.WriteLine(result);21var page = await browser.NewPageAsync();22var expression = "document.querySelector('div').innerText";23var result = await page.MainFrame.EvaluateExpressionAsync<string>(expression);24Console.WriteLine(result);25var page = await browser.NewPageAsync();26var expression = "document.querySelector('div').innerText";27var result = await page.MainFrame.EvaluateExpressionAsync<string>(expression);28Console.WriteLine(result);

EvaluateExpressionAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);9            var browser = await Puppeteer.LaunchAsync(new LaunchOptions10            {11            });12            var page = await browser.NewPageAsync();13            var jsCode = "var x = 5;var y = 6;var z = x + y;";14            await page.EvaluateExpressionAsync(jsCode);15            var jsVariable = await page.EvaluateExpressionAsync("z");16            Console.WriteLine(jsVariable);17            var jsFunction = await page.EvaluateExpressionAsync("function add(a, b) {return a + b;}");18            Console.WriteLine(jsFunction);19            await browser.CloseAsync();20        }21    }22}23function add(a, b) {return a + b;}24using System;25using System.Threading.Tasks;26using PuppeteerSharp;27{28    {29        static async Task Main(string[] args)30        {31            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);32            var browser = await Puppeteer.LaunchAsync(new LaunchOptions33            {34            });

EvaluateExpressionAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            var browser = await Puppeteer.LaunchAsync(new LaunchOptions9            {10            });11            var page = await browser.NewPageAsync();12            var result = await page.EvaluateExpressionAsync<int>("1 + 2");13            Console.WriteLine($"Result: {result}");14            await browser.CloseAsync();15        }16    }17}18using System;19using System.Threading.Tasks;20using PuppeteerSharp;21{22    {23        static async Task Main(string[] args)24        {25            var browser = await Puppeteer.LaunchAsync(new LaunchOptions26            {27            });28            var page = await browser.NewPageAsync();29            var result = await page.EvaluateExpressionAsync<int>("1 + 2").ConfigureAwait(false);30            Console.WriteLine($"

EvaluateExpressionAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            var browser = await Puppeteer.LaunchAsync(new LaunchOptions9            {10                ExecutablePath = @"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe"11            });12            var page = await browser.NewPageAsync();13            var result = await page.EvaluateExpressionAsync<string>("document.title");14            Console.WriteLine(result);15            Console.WriteLine("Press any key to close the browser");16            Console.ReadKey();17            await browser.CloseAsync();18        }19    }20}21using System;22using System.Threading.Tasks;23using PuppeteerSharp;24{25    {26        static async Task Main(string[] args)27        {28            var browser = await Puppeteer.LaunchAsync(new LaunchOptions29            {30                ExecutablePath = @"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe"31            });32            var page = await browser.NewPageAsync();33            var result = await page.EvaluateExpressionAsync<string>("document.title");34            Console.WriteLine(result);35            Console.WriteLine("Press any key to close the browser");36            Console.ReadKey();37            await browser.CloseAsync();38        }39    }40}41using System;42using System.Threading.Tasks;43using PuppeteerSharp;44{45    {46        static async Task Main(string[] args)47        {

Automation Testing Tutorials

Learn to execute automation testing from scratch with LambdaTest Learning Hub. Right from setting up the prerequisites to run your first automation test, to following best practices and diving deeper into advanced test scenarios. LambdaTest Learning Hubs compile a list of step-by-step guides to help you be proficient with different test automation frameworks i.e. Selenium, Cypress, TestNG etc.