How to use EvaluateExpressionHandleAsync method of PuppeteerSharp.Frame class

Best Puppeteer-sharp code snippet using PuppeteerSharp.Frame.EvaluateExpressionHandleAsync

Page.cs

Source:Page.cs

...329        /// <remarks>330        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.331        /// </remarks>332        /// <returns>Task which resolves to script return value</returns>333        public async Task<JSHandle> EvaluateExpressionHandleAsync(string script)334        {335            var context = await MainFrame.GetExecutionContextAsync().ConfigureAwait(false);336            return await context.EvaluateExpressionHandleAsync(script).ConfigureAwait(false);337        }338        /// <summary>339        /// Executes a script in browser context340        /// </summary>341        /// <param name="pageFunction">Script to be evaluated in browser context</param>342        /// <param name="args">Function arguments</param>343        /// <remarks>344        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.345        /// <see cref="JSHandle"/> instances can be passed as arguments346        /// </remarks>347        /// <returns>Task which resolves to script return value</returns>348        public async Task<JSHandle> EvaluateFunctionHandleAsync(string pageFunction, params object[] args)349        {350            var context = await MainFrame.GetExecutionContextAsync().ConfigureAwait(false);...

Frame.cs

Source:Frame.cs

...192        /// <seealso cref="EvaluateExpressionAsync{T}(string)"/>193        /// <seealso cref="Page.EvaluateFunctionAsync{T}(string, object[])"/>194        public Task<T> EvaluateFunctionAsync<T>(string script, params object[] args) => MainWorld.EvaluateFunctionAsync<T>(script, args);195        /// <summary>196        /// Passes an expression to the <see cref="ExecutionContext.EvaluateExpressionHandleAsync(string)"/>, returns a <see cref="Task"/>, then <see cref="ExecutionContext.EvaluateExpressionHandleAsync(string)"/> would wait for the <see cref="Task"/> to resolve and return its value.197        /// </summary>198        /// <example>199        /// <code>200        /// var frame = page.MainFrame;201        /// const handle = Page.MainFrame.EvaluateExpressionHandleAsync("1 + 2");202        /// </code>203        /// </example>204        /// <returns>Resolves to the return value of <paramref name="script"/></returns>205        /// <param name="script">Expression to be evaluated in the <seealso cref="ExecutionContext"/></param>206        public Task<JSHandle> EvaluateExpressionHandleAsync(string script) => MainWorld.EvaluateExpressionHandleAsync(script);207        /// <summary>208        /// Passes a function to the <see cref="ExecutionContext.EvaluateFunctionAsync(string, object[])"/>, returns a <see cref="Task"/>, then <see cref="ExecutionContext.EvaluateFunctionHandleAsync(string, object[])"/> would wait for the <see cref="Task"/> to resolve and return its value.209        /// </summary>210        /// <example>211        /// <code>212        /// var frame = page.MainFrame;213        /// const handle = Page.MainFrame.EvaluateFunctionHandleAsync("() => Promise.resolve(self)");214        /// return handle; // Handle for the global object.215        /// </code>216        /// <see cref="JSHandle"/> instances can be passed as arguments to the <see cref="ExecutionContext.EvaluateFunctionAsync(string, object[])"/>:217        /// 218        /// const handle = await Page.MainFrame.EvaluateExpressionHandleAsync("document.body");219        /// const resultHandle = await Page.MainFrame.EvaluateFunctionHandleAsync("body => body.innerHTML", handle);220        /// return await resultHandle.JsonValueAsync(); // prints body's innerHTML221        /// </example>222        /// <returns>Resolves to the return value of <paramref name="function"/></returns>223        /// <param name="function">Function to be evaluated in the <see cref="ExecutionContext"/></param>224        /// <param name="args">Arguments to pass to <paramref name="function"/></param>225        public Task<JSHandle> EvaluateFunctionHandleAsync(string function, params object[] args) => MainWorld.EvaluateFunctionHandleAsync(function, args);226        /// <summary>227        /// Gets the <see cref="ExecutionContext"/> associated with the frame.228        /// </summary>229        /// <returns><see cref="ExecutionContext"/> associated with the frame.</returns>230        public Task<ExecutionContext> GetExecutionContextAsync() => MainWorld.GetExecutionContextAsync();231        /// <summary>232        /// Waits for a selector to be added to the DOM...

DOMWorld.cs

Source:DOMWorld.cs

...55                throw new PuppeteerException($"Execution Context is not available in detached frame \"{Frame.Url}\"(are you trying to evaluate?)");56            }57            return _contextResolveTaskWrapper.Task;58        }59        internal async Task<JSHandle> EvaluateExpressionHandleAsync(string script)60        {61            var context = await GetExecutionContextAsync().ConfigureAwait(false);62            return await context.EvaluateExpressionHandleAsync(script).ConfigureAwait(false);63        }64        internal async Task<JSHandle> EvaluateFunctionHandleAsync(string script, params object[] args)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();264            var timeout = options.Timeout ?? _timeoutSettings.Timeout;265            const string predicate = @"266              function predicate(selectorOrXPath, isXPath, waitForVisible, waitForHidden) {267                const node = isXPath268                  ? document.evaluate(selectorOrXPath, document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue269                  : document.querySelector(selectorOrXPath);270                if (!node)...

ExecutionContext.cs

Source:ExecutionContext.cs

...42        /// <remarks>43        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.44        /// </remarks>45        /// <seealso cref="EvaluateFunctionAsync{T}(string, object[])"/>46        /// <seealso cref="EvaluateExpressionHandleAsync(string)"/>47        /// <returns>Task which resolves to script return value</returns>48        public Task<JToken> EvaluateExpressionAsync(string script)49            => EvaluateAsync<JToken>(EvaluateExpressionHandleAsync(script));50        /// <summary>51        /// Executes a script in browser context52        /// </summary>53        /// <typeparam name="T">The type to deserialize the result to</typeparam>54        /// <param name="script">Script to be evaluated in browser context</param>55        /// <remarks>56        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.57        /// </remarks>58        /// <seealso cref="EvaluateFunctionAsync{T}(string, object[])"/>59        /// <seealso cref="EvaluateExpressionHandleAsync(string)"/>60        /// <returns>Task which resolves to script return value</returns>61        public Task<T> EvaluateExpressionAsync<T>(string script)62            => EvaluateAsync<T>(EvaluateExpressionHandleAsync(script));63        /// <summary>64        /// Executes a function in browser context65        /// </summary>66        /// <param name="script">Script to be evaluated in browser context</param>67        /// <param name="args">Arguments to pass to script</param>68        /// <remarks>69        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.70        /// <see cref="JSHandle"/> instances can be passed as arguments71        /// </remarks>72        /// <seealso cref="EvaluateExpressionAsync{T}(string)"/>73        /// <seealso cref="EvaluateFunctionHandleAsync(string, object[])"/>74        /// <returns>Task which resolves to script return value</returns>75        public Task<JToken> EvaluateFunctionAsync(string script, params object[] args)76            => EvaluateAsync<JToken>(EvaluateFunctionHandleAsync(script, args));77        /// <summary>78        /// Executes a function in browser context79        /// </summary>80        /// <typeparam name="T">The type to deserialize the result to</typeparam>81        /// <param name="script">Script to be evaluated in browser context</param>82        /// <param name="args">Arguments to pass to script</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        /// <see cref="JSHandle"/> instances can be passed as arguments86        /// </remarks>87        /// <seealso cref="EvaluateExpressionAsync{T}(string)"/>88        /// <seealso cref="EvaluateFunctionHandleAsync(string, object[])"/>89        /// <returns>Task which resolves to script return value</returns>90        public Task<T> EvaluateFunctionAsync<T>(string script, params object[] args)91            => EvaluateAsync<T>(EvaluateFunctionHandleAsync(script, args));92        /// <summary>93        /// The method iterates JavaScript heap and finds all the objects with the given prototype.94        /// </summary>95        /// <returns>A task which resolves to a handle to an array of objects with this prototype.</returns>96        /// <param name="prototypeHandle">A handle to the object prototype.</param>97        public async Task<JSHandle> QueryObjectsAsync(JSHandle prototypeHandle)98        {99            if (prototypeHandle.Disposed)100            {101                throw new PuppeteerException("Prototype JSHandle is disposed!");102            }103            if (!((JObject)prototypeHandle.RemoteObject).TryGetValue(MessageKeys.ObjectId, out var objectId))104            {105                throw new PuppeteerException("Prototype JSHandle must not be referencing primitive value");106            }107            var response = await _client.SendAsync("Runtime.queryObjects", new Dictionary<string, object>108            {109                {"prototypeObjectId", objectId.ToString()}110            }).ConfigureAwait(false);111            return CreateJSHandle(response[MessageKeys.Objects]);112        }113        internal async Task<JSHandle> EvaluateExpressionHandleAsync(string script)114        {115            if (string.IsNullOrEmpty(script))116            {117                return null;118            }119            try120            {121                return await EvaluateHandleAsync("Runtime.evaluate", new Dictionary<string, object>122                {123                    ["expression"] = _sourceUrlRegex.IsMatch(script) ? script : $"{script}\n{EvaluationScriptSuffix}",124                    ["contextId"] = _contextId,125                    ["returnByValue"] = false,126                    ["awaitPromise"] = true,127                    ["userGesture"] = true...

NetworkEventTests.cs

Source:NetworkEventTests.cs

...34            await Page.GoToAsync(TestConstants.EmptyPage);35            Server.SetRoute("/post", context => Task.CompletedTask);36            Request request = null;37            Page.Request += (sender, e) => request = e.Request;38            await Page.EvaluateExpressionHandleAsync("fetch('./post', { method: 'POST', body: JSON.stringify({ foo: 'bar'})})");39            Assert.NotNull(request);40            Assert.Equal("{\"foo\":\"bar\"}", request.PostData);41        }42        [Fact]43        public async Task PageEventsResponse()44        {45            var responses = new List<Response>();46            Page.Response += (sender, e) => responses.Add(e.Response);47            await Page.GoToAsync(TestConstants.EmptyPage);48            Assert.Single(responses);49            Assert.Equal(TestConstants.EmptyPage, responses[0].Url);50            Assert.Equal(HttpStatusCode.OK, responses[0].Status);51            Assert.NotNull(responses[0].Request);52        }...

EvaluateTests.cs

Source:EvaluateTests.cs

...129        }130        [Fact]131        public async Task ShouldAcceptObjectHandleAsAnArgument()132        {133            var navigatorHandle = await Page.EvaluateExpressionHandleAsync("navigator");134            var text = await Page.EvaluateFunctionAsync<string>("e => e.userAgent", navigatorHandle);135            Assert.Contains("Mozilla", text);136        }137        [Fact]138        public async Task ShouldAcceptObjectHandleToPrimitiveTypes()139        {140            var aHandle = await Page.EvaluateExpressionHandleAsync("5");141            var isFive = await Page.EvaluateFunctionAsync<bool>("e => Object.is(e, 5)", aHandle);142            Assert.True(isFive);143        }144        [Fact]145        public async Task ShouldWorkFromInsideAnExposedFunction()146        {147            await Page.ExposeFunctionAsync("callController", async (int a, int b) =>148            {149                return await Page.EvaluateFunctionAsync("(a, b) => a * b", a, b);150            });151            var result = await Page.EvaluateFunctionAsync<int>(@"async function() {152                return await callController(9, 3);153            }");154            Assert.Equal(27, result);...

PuppeteerExtensions.cs

Source:PuppeteerExtensions.cs

...7		#region Methods8		public static async Task<ElementHandle> QuerySelectorByXPath(this Page page, string xpath)9		{10			var script = $"document.evaluate('{xpath}', document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue;";11			var handle = await page.EvaluateExpressionHandleAsync(script).ConfigureAwait(false);12			if (handle is ElementHandle element)13			{14				return element;15			}16			await handle.DisposeAsync().ConfigureAwait(false);17			return null;18		}19		20		public static async Task<ElementHandle> QuerySelectorByXPath(this Frame frame, string xpath)21		{22			var script = $"document.evaluate('{xpath}', document, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue;";23			var handle = await frame.EvaluateExpressionHandleAsync(script).ConfigureAwait(false);24			if (handle is ElementHandle element)25			{26				return element;27			}28			await handle.DisposeAsync().ConfigureAwait(false);29			return null;30		}31		#endregion32	}33}...

EvaluateHandleTests.cs

Source:EvaluateHandleTests.cs

...16        [PuppeteerFact]17        public async Task ShouldWork()18        {19            await Page.GoToAsync(TestConstants.EmptyPage);20            var windowHandle = await Page.MainFrame.EvaluateExpressionHandleAsync("window");21            Assert.NotNull(windowHandle);22        }23    }24}...

EvaluateExpressionHandleAsync

Using AI Code Generation

1public static async Task EvaluateExpressionHandleAsyncExample()2{3    var options = new LaunchOptions { Headless = false };4    using (var browser = await Puppeteer.LaunchAsync(options))5    using (var page = await browser.NewPageAsync())6    {7        var elementHandle = await page.EvaluateExpressionHandleAsync("document");8        Console.WriteLine(elementHandle);9    }10}11public static async Task EvaluateFunctionHandleAsyncExample()12{13    var options = new LaunchOptions { Headless = false };14    using (var browser = await Puppeteer.LaunchAsync(options))15    using (var page = await browser.NewPageAsync())16    {17        var elementHandle = await page.EvaluateFunctionHandleAsync("() => document");18        Console.WriteLine(elementHandle);19    }20}21public static async Task EvaluateFunctionHandleAsyncExample()22{23    var options = new LaunchOptions { Headless = false };24    using (var browser = await Puppeteer.LaunchAsync(options))25    using (var page = await browser.NewPageAsync())26    {27        var elementHandle = await page.EvaluateFunctionHandleAsync("function() { return document; }");28        Console.WriteLine(elementHandle);29    }30}31public static async Task EvaluateFunctionHandleAsyncExample()32{33    var options = new LaunchOptions { Headless = false };34    using (var browser = await Puppeteer.LaunchAsync(options))35    using (var page = await browser.NewPageAsync())36    {37        var elementHandle = await page.EvaluateFunctionHandleAsync("() => { return document; }");38        Console.WriteLine(elementHandle);39    }40}41public static async Task EvaluateFunctionHandleAsyncExample()42{43    var options = new LaunchOptions { Headless = false };44    using (var browser = await Puppeteer.LaunchAsync(options))

EvaluateExpressionHandleAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static void Main(string[] args)7        {8            MainAsync().Wait();9        }10        static async Task MainAsync()11        {12            {13            };14            var browser = await Puppeteer.LaunchAsync(options);15            var page = await browser.NewPageAsync();16            await page.WaitForSelectorAsync("input[name='q']");17            var handle = await page.EvaluateExpressionHandleAsync("document");18            Console.WriteLine(handle);19            await browser.CloseAsync();20        }21    }22}23using System;24using System.Threading.Tasks;25using PuppeteerSharp;26{27    {28        static void Main(string[] args)29        {30            MainAsync().Wait();31        }32        static async Task MainAsync()33        {34            {35            };36            var browser = await Puppeteer.LaunchAsync(options);37            var page = await browser.NewPageAsync();38            await page.WaitForSelectorAsync("input[name='q']");39            var handle = await page.EvaluateExpressionHandleAsync("document.querySelector('input')");40            Console.WriteLine(handle);41            await browser.CloseAsync();42        }43    }44}

EvaluateExpressionHandleAsync

Using AI Code Generation

1var page = await browser.NewPageAsync();2var handle = await page.EvaluateExpressionHandleAsync("document.body");3var properties = await handle.GetPropertiesAsync();4var values = await Task.WhenAll(properties.Values.Select(x => x.JsonValueAsync()));5foreach (var value in values)6{7    Console.WriteLine(value);8}9await browser.CloseAsync();10var page = await browser.NewPageAsync();11var handle = await page.EvaluateExpressionHandleAsync("document.body");12var properties = await handle.GetPropertiesAsync();13var values = await Task.WhenAll(properties.Values.Select(x => x.JsonValueAsync()));14foreach (var value in values)15{16    Console.WriteLine(value);17}18await browser.CloseAsync();19var page = await browser.NewPageAsync();20var handle = await page.EvaluateExpressionHandleAsync("document.body");21var properties = await handle.GetPropertiesAsync();22var values = await Task.WhenAll(properties.Values.Select(x => x.JsonValueAsync()));23foreach (var value in values)24{25    Console.WriteLine(value);26}27await browser.CloseAsync();28var page = await browser.NewPageAsync();29var handle = await page.EvaluateExpressionHandleAsync("document.body");30var properties = await handle.GetPropertiesAsync();31var values = await Task.WhenAll(properties.Values.Select(x => x.JsonValueAsync()));32foreach (var value in values)33{34    Console.WriteLine(value);35}36await browser.CloseAsync();37var page = await browser.NewPageAsync();38var handle = await page.EvaluateExpressionHandleAsync("document.body");39var properties = await handle.GetPropertiesAsync();40var values = await Task.WhenAll(properties.Values.Select(x => x.JsonValueAsync()));41foreach (var value in values)42{43    Console.WriteLine(value);44}45await browser.CloseAsync();

EvaluateExpressionHandleAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            {9            };10            using (var browser = await Puppeteer.LaunchAsync(options))11            using (var page = await browser.NewPageAsync())12            {13                var expression = "document.querySelector('p')";14                var handle = await page.MainFrame.EvaluateExpressionHandleAsync(expression);15                Console.WriteLine(handle);16            }17        }18    }19}20using System;21using System.Threading.Tasks;22using PuppeteerSharp;23{24    {25        static async Task Main(string[] args)26        {27            {28            };29            using (var browser = await Puppeteer.LaunchAsync(options))30            using (var page = await browser.NewPageAsync())31            {32                var expression = "document.querySelector('p')";33                var handle = await page.MainFrame.EvaluateExpressionHandleAsync(expression);34                var result = await handle.JsonValueAsync();35                Console.WriteLine(result);36            }37        }38    }39}40using System;41using System.Threading.Tasks;42using PuppeteerSharp;43{44    {45        static async Task Main(string[] args)46        {47            {48            };49            using (var browser = await Puppeteer.LaunchAsync(options))50            using (var page = await browser.NewPageAsync())51            {

EvaluateExpressionHandleAsync

Using AI Code Generation

1var frame = await page.GetMainFrameAsync();2var handle = await frame.EvaluateExpressionHandleAsync("document.querySelector('div')");3var element = (ElementHandle)handle;4var result = await element.EvaluateFunctionAsync<string>("element => element.nodeName");5Console.WriteLine(result);6var frame = await page.GetMainFrameAsync();7var handle = await page.EvaluateExpressionHandleAsync("document.querySelector('div')");8var element = (ElementHandle)handle;9var result = await element.EvaluateFunctionAsync<string>("element => element.nodeName");10Console.WriteLine(result);11Your name to display (optional):12Your name to display (optional):13var frame = await page.GetMainFrameAsync();14var handle = await frame.EvaluateExpressionHandleAsync("document.querySelector('div')");15var element = (ElementHandle)handle;16var result = await element.EvaluateFunctionAsync<string>("element => element.nodeName");17Console.WriteLine(result);18Your name to display (optional):

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