How to use EvaluateFunctionAsync method of PuppeteerSharp.JSHandle class

Best Puppeteer-sharp code snippet using PuppeteerSharp.JSHandle.EvaluateFunctionAsync

ExecutionContext.cs

Source:ExecutionContext.cs

...43        /// <param name="script">Script to be evaluated in browser context</param>44        /// <remarks>45        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.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            {103                throw new PuppeteerException("Prototype JSHandle is disposed!");104            }...

PageCTL.cs

Source:PageCTL.cs

...120        public async Task<bool> WaitForPropertyAsync(string selector, string property, object value, int timeout = 30000)121        {122            do123            {124                bool success = await mPage.EvaluateFunctionAsync<bool>(@"125                (selector, property, value) => {126                    const ele = document.querySelector(selector);127                    if (ele == null) return false;128                    return ele[property] == value;129                }", selector, property, value);130                if (success)131                {132                    return true;133                }134                await Task.Delay(3000);135                timeout -= 3000;136            }137            while (timeout > 0);138            return false;139        }140        public async Task<bool> WaitForElementAsync(string selector, Func<ElementHandle, bool> func, int timeout = 30000)141        {142            do143            {144                ElementHandle element;145                try146                {147                    element = await mPage.QuerySelectorAsync(selector);148                    149                }150                catch (Exception ex)151                {152                    Console.WriteLine(ex.Message);153                    element = null;154                }155                if (element != null && func(element))156                {157                    return true;158                }159                await Task.Delay(1000);160                timeout -= 1000;161            } while (timeout > 0);162            return false;163        }164        public async Task<bool> StopLoadingAsync()165        {166            try167            {168                await mPage.EvaluateExpressionAsync("window.stop()");169                return true;170            }171            catch172            {173                return false;174            }175        }176        public async Task<bool> SetInputValueAsync(string selector, string value)177        {178            try179            {180                await mPage.EvaluateFunctionAsync(@"181                (selector, value) => {182                    const ele = document.querySelector(selector);183                    if (ele != null) ele.value = value;184                }", selector, value);185                return true;186            }187            catch188            {189                return false;190            }191        }192        public async Task<string> GetInputValueAsync(string selector)193        {194            try195            {196                return await mPage.EvaluateFunctionAsync<string>(@"197                (selector) => {198                    const ele = document.querySelector(selector);199                    if (ele != null)200                    {201                        return ele.value;202                    }203                    else204                    {205                        return null;206                    }207                }", selector);208            }209            catch210            {211                return null;212            }213        }214        public async Task<bool> SetElementsIDAsync(string selector, string name, int start_index = 0)215        {216            try217            {218                await mPage.EvaluateFunctionAsync(@"219                (selector, name, start_index) => {220                    const eles = document.querySelectorAll(selector);221                    for(var i = 0; i < eles.length; i++) {222                        const ele = eles[i];223                        ele.id = name.concat(start_index + i);224                    }225                }", selector, name, start_index);226                return true;227            }228            catch229            {230                return false;231            }232        }233        public async Task<bool> SetChildsIDAsync(string selector, string name, int start_index = 0)234        {235            try236            {237                return await mPage.EvaluateFunctionAsync<bool>(@"238                (selector, name, start_index) => {239                    const parent = document.querySelector(selector);240                    if (parent == null) return false;241                    const eles = parent.children;242                    for(var i = 0; i < eles.length; i++) {243                        const ele = eles[i];244                        ele.id = name.concat(i);245                    }246                    return true;247                }", selector, name, start_index);248            }249            catch250            {251                return false;252            }253        }254        public async Task<string> GetElementInnerHTML(string selector)255        {256            try257            {258                ElementHandle element = await mPage.QuerySelectorAsync(selector);259                JSHandle handler = await element.GetPropertyAsync("innerHTML");260                return handler.ToString().Replace("JSHandle:", string.Empty);261            }262            catch263            {264                return null;265            }266        }267        public async Task<string> GetElementInnerText(string selector)268        {269            try270            {271                ElementHandle element = await mPage.QuerySelectorAsync(selector);272                JSHandle handler = await element.GetPropertyAsync("innerText");273                return handler.ToString().Replace("JSHandle:", string.Empty);274            }275            catch276            {277                return null;278            }279        }280        public async Task<string[]> GetElementClassListAsynct(string selector)281        {282            try283            {284                ElementHandle element = await mPage.QuerySelectorAsync(selector);285                JSHandle handler = await element.GetPropertyAsync("classList");286                Dictionary<string, string> value = await handler.JsonValueAsync<Dictionary<string, string>>();287                string[] result = new string[value.Count];288                value.Values.CopyTo(result, 0);289                return result;290            }291            catch292            {293                return null;294            }295        }296        public async Task<string> GetElementClassStringAsync(string selector)297        {298            try299            {300                ElementHandle element = await mPage.QuerySelectorAsync(selector);301                JSHandle handler = await element.GetPropertyAsync("classList");302                object value = await handler.JsonValueAsync();303                return value.ToString();304            }305            catch306            {307                return null;308            }309        }310        public async Task<string> GetURLAsync(int times = 3, int delay = 3000)311        {312            do313            {314                try315                {316                    return await mPage.EvaluateFunctionAsync<string>(@"317                    () => {318                        return document.URL;319                    }");320                }321                catch322                {323                    await Task.Delay(delay);324                    times--;325                }326            }327            while (times > 0);328            return mPage.Url;329        }330    }...

JSHandle.cs

Source:JSHandle.cs

...169        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.170        /// <see cref="JSHandle"/> instances can be passed as arguments171        /// </remarks>172        /// <returns>Task which resolves to script return value</returns>173        public Task<JToken> EvaluateFunctionAsync(string script, params object[] args)174        {175            var list = new List<object>(args);176            list.Insert(0, this);177            return ExecutionContext.EvaluateFunctionAsync<JToken>(script, list.ToArray());178        }179        /// <summary>180        /// Executes a function in browser context181        /// </summary>182        /// <typeparam name="T">The type to deserialize the result to</typeparam>183        /// <param name="script">Script to be evaluated in browser context</param>184        /// <param name="args">Arguments to pass to script</param>185        /// <remarks>186        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.187        /// <see cref="JSHandle"/> instances can be passed as arguments188        /// </remarks>189        /// <returns>Task which resolves to script return value</returns>190        public Task<T> EvaluateFunctionAsync<T>(string script, params object[] args)191        {192            var list = new List<object>(args);193            list.Insert(0, this);194            return ExecutionContext.EvaluateFunctionAsync<T>(script, list.ToArray());195        }196        internal object FormatArgument(ExecutionContext context)197        {198            if (ExecutionContext != context)199            {200                throw new PuppeteerException("JSHandles can be evaluated only in the context they were created!");201            }202            if (Disposed)203            {204                throw new PuppeteerException("JSHandle is disposed!");205            }206            var unserializableValue = RemoteObject.UnserializableValue;207            if (unserializableValue != null)208            {...

Worker.cs

Source:Worker.cs

...86        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.87        /// <see cref="JSHandle"/> instances can be passed as arguments88        /// </remarks>89        /// <returns>Task which resolves to script return value</returns>90        public async Task<JToken> EvaluateFunctionAsync(string script, params object[] args)91            => await (await ExecutionContextTask.ConfigureAwait(false)).EvaluateFunctionAsync(script, args).ConfigureAwait(false);92        /// <summary>93        /// Executes a function in the context94        /// </summary>95        /// <typeparam name="T">The type to deserialize the result to</typeparam>96        /// <param name="script">Script to be evaluated in browser context</param>97        /// <param name="args">Arguments to pass to script</param>98        /// <remarks>99        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.100        /// <see cref="JSHandle"/> instances can be passed as arguments101        /// </remarks>102        /// <returns>Task which resolves to script return value</returns>103        public async Task<T> EvaluateFunctionAsync<T>(string script, params object[] args)104            => await (await ExecutionContextTask.ConfigureAwait(false)).EvaluateFunctionAsync<T>(script, args).ConfigureAwait(false);105        /// <summary>106        /// Executes a script in browser context107        /// </summary>108        /// <param name="script">Script to be evaluated in browser context</param>109        /// <remarks>110        /// If the script, returns a Promise, then the method would wait for the promise to resolve and return its value.111        /// </remarks>112        /// <returns>Task which resolves to script return value</returns>113        /// <seealso cref="ExecutionContext.EvaluateExpressionHandleAsync(string)"/>114        public async Task<JSHandle> EvaluateExpressionHandleAsync(string script)115            => await (await ExecutionContextTask.ConfigureAwait(false)).EvaluateExpressionHandleAsync(script).ConfigureAwait(false);116        internal Task<ExecutionContext> ExecutionContextTask => _executionContextCallback.Task;117        internal async void OnMessageReceived(object sender, MessageEventArgs e)118        {...

Extensions.cs

Source:Extensions.cs

...13        /// <param name="pageFunction">Function to be evaluated in browser context</param>14        /// <param name="args">Arguments to pass to <c>pageFunction</c></param>15        /// <returns>Task</returns>16        /// <exception cref="SelectorException">If <paramref name="elementHandleTask"/> resolves to <c>null</c></exception>17        public static Task EvaluateFunctionAsync(this Task<ElementHandle> elementHandleTask, string pageFunction, params object[] args)18            => elementHandleTask.EvaluateFunctionAsync<object>(pageFunction, args);19        /// <summary>20        /// Runs <paramref name="pageFunction"/> within the frame and passes it the outcome of <paramref name="elementHandleTask"/> as the first argument21        /// </summary>22        /// <typeparam name="T">The type of the response</typeparam>23        /// <param name="elementHandleTask">A task that returns an <see cref="ElementHandle"/> that will be used as the first argument in <paramref name="pageFunction"/></param>24        /// <param name="pageFunction">Function to be evaluated in browser context</param>25        /// <param name="args">Arguments to pass to <c>pageFunction</c></param>26        /// <returns>Task which resolves to the return value of <c>pageFunction</c></returns>27        /// <exception cref="SelectorException">If <paramref name="elementHandleTask"/> resolves to <c>null</c></exception>28        public static async Task<T> EvaluateFunctionAsync<T>(this Task<ElementHandle> elementHandleTask, string pageFunction, params object[] args)29        {30            var elementHandle = await elementHandleTask.ConfigureAwait(false);31            if (elementHandle == null)32            {33                throw new SelectorException("Error: failed to find element matching selector");34            }35            return await elementHandle.EvaluateFunctionAsync<T>(pageFunction, args).ConfigureAwait(false);36        }37        /// <summary>38        /// Runs <paramref name="pageFunction"/> within the frame and passes it the outcome the <paramref name="elementHandle"/> as the first argument39        /// </summary>40        /// <typeparam name="T">The type of the response</typeparam>41        /// <param name="elementHandle">An <see cref="ElementHandle"/> that will be used as the first argument in <paramref name="pageFunction"/></param>42        /// <param name="pageFunction">Function to be evaluated in browser context</param>43        /// <param name="args">Arguments to pass to <c>pageFunction</c></param>44        /// <returns>Task which resolves to the return value of <c>pageFunction</c></returns>45        /// <exception cref="SelectorException">If <paramref name="elementHandle"/> is <c>null</c></exception>46        public static async Task<T> EvaluateFunctionAsync<T>(this ElementHandle elementHandle, string pageFunction, params object[] args)47        {48            if (elementHandle == null)49            {50                throw new SelectorException("Error: failed to find element matching selector");51            }52            var newArgs = new object[args.Length + 1];53            newArgs[0] = elementHandle;54            args.CopyTo(newArgs, 1);55            var result = await elementHandle.ExecutionContext.EvaluateFunctionAsync<T>(pageFunction, newArgs).ConfigureAwait(false);56            await elementHandle.DisposeAsync().ConfigureAwait(false);57            return result;58        }59        /// <summary>60        /// Runs <paramref name="pageFunction"/> within the frame and passes it the outcome of <paramref name="arrayHandleTask"/> as the first argument. Use only after <see cref="Page.QuerySelectorAllHandleAsync(string)"/>61        /// </summary>62        /// <param name="arrayHandleTask">A task that returns an <see cref="JSHandle"/> that represents an array of <see cref="ElementHandle"/> that will be used as the first argument in <paramref name="pageFunction"/></param>63        /// <param name="pageFunction">Function to be evaluated in browser context</param>64        /// <param name="args">Arguments to pass to <c>pageFunction</c></param>65        /// <returns>Task</returns>66        public static Task EvaluateFunctionAsync(this Task<JSHandle> arrayHandleTask, string pageFunction, params object[] args)67            => arrayHandleTask.EvaluateFunctionAsync<object>(pageFunction, args);68        /// <summary>69        /// Runs <paramref name="pageFunction"/> within the frame and passes it the outcome of <paramref name="arrayHandleTask"/> as the first argument. Use only after <see cref="Page.QuerySelectorAllHandleAsync(string)"/>70        /// </summary>71        /// <typeparam name="T"></typeparam>72        /// <param name="arrayHandleTask">A task that returns an <see cref="JSHandle"/> that represents an array of <see cref="ElementHandle"/> that will be used as the first argument in <paramref name="pageFunction"/></param>73        /// <param name="pageFunction">Function to be evaluated in browser context</param>74        /// <param name="args">Arguments to pass to <c>pageFunction</c></param>75        /// <returns>Task which resolves to the return value of <c>pageFunction</c></returns>76        public static async Task<T> EvaluateFunctionAsync<T>(this Task<JSHandle> arrayHandleTask, string pageFunction, params object[] args)77            => await (await arrayHandleTask.ConfigureAwait(false)).EvaluateFunctionAsync<T>(pageFunction, args).ConfigureAwait(false);78        /// <summary>79        /// Runs <paramref name="pageFunction"/> within the frame and passes it the outcome of <paramref name="arrayHandle"/> as the first argument. Use only after <see cref="Page.QuerySelectorAllHandleAsync(string)"/>80        /// </summary>81        /// <typeparam name="T"></typeparam>82        /// <param name="arrayHandle">An <see cref="JSHandle"/> that represents an array of <see cref="ElementHandle"/> that will be used as the first argument in <paramref name="pageFunction"/></param>83        /// <param name="pageFunction">Function to be evaluated in browser context</param>84        /// <param name="args">Arguments to pass to <c>pageFunction</c></param>85        /// <returns>Task which resolves to the return value of <c>pageFunction</c></returns>86        public static async Task<T> EvaluateFunctionAsync<T>(this JSHandle arrayHandle, string pageFunction, params object[] args)87        {88            var response = await arrayHandle.JsonValueAsync<object[]>().ConfigureAwait(false);89            var newArgs = new object[args.Length + 1];90            newArgs[0] = arrayHandle;91            args.CopyTo(newArgs, 1);92            var result = await arrayHandle.ExecutionContext.EvaluateFunctionAsync<T>(pageFunction, newArgs).ConfigureAwait(false);93            await arrayHandle.DisposeAsync().ConfigureAwait(false);94            return result;95        }96    }97}...

BookReSellService.cs

Source:BookReSellService.cs

...142            foreach (var element in elementHandles)143            {144                //var jsHandle = await element.GetPropertyAsync("dataset");145                //var price = await element.GetPropertyAsync("dataset.price");146                var price = decimal.Parse(await element.EvaluateFunctionAsync<string>("(el) => el.getAttribute(\"data-price\")", element));147                var vendorId = await element.EvaluateFunctionAsync<string>("(el) => el.getAttribute(\"data-vendorid\")", element);148                var vendorName = await element.EvaluateFunctionAsync<string>("(el) => el.getAttribute(\"data-vendor\")", element);149                VendorResult result = new VendorResult(book, vendorId, vendorName, price);150                //Console.WriteLine(result.ToString());151                vendorResults.Add(result);152            }153        }154        static string TrimElementHandlerPropertyString(string elementHandlerPropertyString) => elementHandlerPropertyString.Substring(9);155        static string TrimElementHandlerPropertyString(JSHandle elementHandlerPropertyString) => elementHandlerPropertyString.ToString().Substring(9);156    }157}...

PageEvaluateHandle.cs

Source:PageEvaluateHandle.cs

...19        [PuppeteerFact]20        public async Task ShouldAcceptObjectHandleAsAnArgument()21        {22            var navigatorHandle = await Page.EvaluateFunctionHandleAsync("() => navigator");23            var text = await Page.EvaluateFunctionAsync<string>(24                "(e) => e.userAgent",25                navigatorHandle);26            Assert.Contains("Mozilla", text);27        }28        [PuppeteerTest("jshandle.spec.ts", "Page.evaluateHandle", "should accept object handle to primitive types")]29        [PuppeteerFact]30        public async Task ShouldAcceptObjectHandleToPrimitiveTypes()31        {32            var aHandle = await Page.EvaluateFunctionHandleAsync("() => 5");33            var isFive = await Page.EvaluateFunctionAsync<bool>(34                "(e) => Object.is(e, 5)",35                aHandle);36            Assert.True(isFive);37        }38        [PuppeteerTest("jshandle.spec.ts", "Page.evaluateHandle", "should warn on nested object handles")]39        [PuppeteerFact]40        public async Task ShouldWarnOnNestedObjectHandles()41        {42            var aHandle = await Page.EvaluateFunctionHandleAsync("() => document.body");43            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(() =>44                Page.EvaluateFunctionHandleAsync("(opts) => opts.elem.querySelector('p')", new { aHandle }));45            Assert.Contains("Are you passing a nested JSHandle?", exception.Message);46        }47        [PuppeteerTest("jshandle.spec.ts", "Page.evaluateHandle", "should accept object handle to unserializable value")]48        [PuppeteerFact]49        public async Task ShouldAcceptObjectHandleToUnserializableValue()50        {51            var aHandle = await Page.EvaluateFunctionHandleAsync("() => Infinity");52            Assert.True(await Page.EvaluateFunctionAsync<bool>(53                "(e) => Object.is(e, Infinity)",54                aHandle));55        }56        [PuppeteerTest("jshandle.spec.ts", "Page.evaluateHandle", "should use the same JS wrappers")]57        [PuppeteerFact]58        public async Task ShouldUseTheSameJSWrappers()59        {60            var aHandle = await Page.EvaluateFunctionHandleAsync(@"() => {61                globalThis.FOO = 123;62                return window;63            }");64            Assert.Equal(123, await Page.EvaluateFunctionAsync<int>(65                "(e) => e.FOO",66                aHandle));67        }68    }69}...

QueryObjectsTests.cs

Source:QueryObjectsTests.cs

...15            // Instantiate an object16            await Page.EvaluateExpressionAsync("window.set = new Set(['hello', 'world'])");17            var prototypeHandle = await Page.EvaluateExpressionHandleAsync("Set.prototype");18            var objectsHandle = await Page.QueryObjectsAsync(prototypeHandle);19            var count = await Page.EvaluateFunctionAsync<int>("objects => objects.length", objectsHandle);20            Assert.Equal(1, count);21            var values = await Page.EvaluateFunctionAsync<string[]>("objects => Array.from(objects[0].values())", objectsHandle);22            Assert.Equal(new[] { "hello", "world" }, values);23        }24        [Fact]25        public async Task ShouldFailForDisposedHandles()26        {27            var prototypeHandle = await Page.EvaluateExpressionHandleAsync("HTMLBodyElement.prototype");28            await prototypeHandle.DisposeAsync();29            var exception = await Assert.ThrowsAsync<PuppeteerException>(()30                => Page.QueryObjectsAsync(prototypeHandle));31            Assert.Equal("Prototype JSHandle is disposed!", exception.Message);32        }33        [Fact]34        public async Task ShouldFailPrimitiveValuesAsPrototypes()35        {...

EvaluateFunctionAsync

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 searchBox = await page.QuerySelectorAsync("input[title='Search']");14            await searchBox.TypeAsync("PuppeteerSharp");15            var searchButton = await page.QuerySelectorAsync("input[value='Google Search']");16            await searchButton.ClickAsync();17            var result = await page.EvaluateFunctionAsync<int>("() => document.querySelectorAll('div.g').length");18            Console.WriteLine(result);19            await browser.CloseAsync();20        }21    }22}

EvaluateFunctionAsync

Using AI Code Generation

1using System.Threading.Tasks;2using PuppeteerSharp;3{4    {5        static async Task Main(string[] args)6        {7            var options = new LaunchOptions { Headless = true };8            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);9            using (var browser = await Puppeteer.LaunchAsync(options))10            using (var page = await browser.NewPageAsync())11            {12                var result = await page.EvaluateFunctionAsync<int>("(a, b) => a + b", 1, 2);13            }14        }15    }16}17using System.Threading.Tasks;18using PuppeteerSharp;19{20    {21        static async Task Main(string[] args)22        {23            var options = new LaunchOptions { Headless = true };24            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);25            using (var browser = await Puppeteer.LaunchAsync(options))26            using (var page = await browser.NewPageAsync())27            {28                var result = await page.EvaluateFunctionHandleAsync("() => document.body");29            }30        }31    }32}33using System.Threading.Tasks;34using PuppeteerSharp;35{36    {37        static async Task Main(string[] args)38        {39            var options = new LaunchOptions { Headless = true };40            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);41            using (var browser = await Puppeteer.LaunchAsync(options))42            using (var page = await browser.NewPageAsync())43            {44                var result = await page.EvaluateFunctionHandleAsync("() => document.body");45            }46        }47    }48}

EvaluateFunctionAsync

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            var element = await page.QuerySelectorAsync("input[name='q']");12            var result = await element.EvaluateFunctionAsync("x => x.value");13            Console.WriteLine(result);14            await browser.CloseAsync();15        }16    }17}

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