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How to use EvaluateExpressionHandleAsync method of PuppeteerSharp.Page class

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

GeneratePdf.cs

Source:GeneratePdf.cs

...75                    Width = width,76                    Height = 108077                });78                // dimensions = await page.EvaluateExpressionAsync<string>(jsWidth);79                await page.EvaluateExpressionHandleAsync("document.fonts.ready"); // Wait for fonts to be loaded. Omitting this might result in no text rendered in pdf.80                // use the screen mode for viewing the web page81                await page.EmulateMediaTypeAsync(PuppeteerSharp.Media.MediaType.Screen);82                // define some options83                var options = new PdfOptions()84                {85                    Width = width,86                    Height = 1080,87                    Format = PuppeteerSharp.Media.PaperFormat.Letter,88                    DisplayHeaderFooter = false,89                    PrintBackground = printBackground90                };91                // throws an error if margin is less than 1092                if (margin >= 10)93                {...

Program.cs

Source:Program.cs

...45    output.OutputInAscii("Wordle");46    page = await browser.NewPageAsync();47    await page.GoToAsync(wordleUrl);48    var element = await49        page.EvaluateExpressionHandleAsync(50            "document.querySelector(\"body > game-app\").shadowRoot.querySelector(\"#game > game-modal\")" +51            ".shadowRoot.querySelector(\"div > div > div > game-icon\")" +52            ".shadowRoot.querySelector(\"svg\")") as ElementHandle;53    await Task.Delay(100);54    await element?.ClickAsync()!;55    List<string> colors = new(5);56    var wordle = new Wordle(currentWord);57    var completed = false;58    var attempt = 0;59// number of attempts to find a word - 6 is the max60// also means to increment the row count by 1 to read next word61    for (var i = 1; i < 7; i++)62    {63        await page.TypeAsync("body > game-app", currentWord);...

CheckoutTests.cs

Source:CheckoutTests.cs

...20                var bestPrice = await page.EvaluateFunctionAsync<string>(@"() => {21                    var elements = document.querySelectorAll('.main-content .price-amount');22                    return elements.length ? elements[0].innerText : '0';23                }");24                var clickElement = await page.EvaluateExpressionHandleAsync(@"25                    document.querySelectorAll('.main-content buy-button:first-child A')[0]") as ElementHandle;26                await clickElement.ClickAsync();27                await page.WaitForSelectorAsync(".price-container .amount");28                var checkoutPrice = await page.EvaluateExpressionAsync<string>(@"29                    document.querySelectorAll('.price-container .amount')[0].innerText30                ");31                Assert.Equal(bestPrice, checkoutPrice);32            }33        }34    }35}
...

JsonValueTests.cs

Source:JsonValueTests.cs

...12        }13        [Fact]14        public async Task ShouldWork()15        {16            var aHandle = await Page.EvaluateExpressionHandleAsync("({ foo: 'bar'})");17            var json = await aHandle.JsonValueAsync();18            Assert.Equal(JObject.Parse("{ foo: 'bar' }"), json);19        }20        [Fact]21        public async Task ShouldNotWorkWithDates()22        {23            var dateHandle = await Page.EvaluateExpressionHandleAsync("new Date('2017-09-26T00:00:00.000Z')");24            var json = await dateHandle.JsonValueAsync();25            Assert.Equal(JObject.Parse("{}"), json);26        }27        [Fact]28        public async Task ShouldThrowForCircularObjects()29        {30            var windowHandle = await Page.EvaluateExpressionHandleAsync("window");31            var exception = await Assert.ThrowsAsync<MessageException>(()32                => windowHandle.JsonValueAsync());33            Assert.Contains("Object reference chain is too long", exception.Message);34        }35    }36}...

AsElementTests.cs

Source:AsElementTests.cs

...11        }12        [Fact]13        public async Task ShouldWork()14        {15            var aHandle = await Page.EvaluateExpressionHandleAsync("document.body");16            var element = aHandle as ElementHandle;17            Assert.NotNull(element);18        }19        [Fact]20        public async Task ShouldReturnNullForNonElements()21        {22            var aHandle = await Page.EvaluateExpressionHandleAsync("2");23            var element = aHandle as ElementHandle;24            Assert.Null(element);25        }26        [Fact]27        public async Task ShouldReturnElementHandleForTextNodes()28        {29            await Page.SetContentAsync("<div>ee!</div>");30            var aHandle = await Page.EvaluateExpressionHandleAsync("document.querySelector('div').firstChild");31            var element = aHandle as ElementHandle;32            Assert.NotNull(element);33            Assert.NotNull(await Page.EvaluateFunctionAsync("e => e.nodeType === HTMLElement.TEXT_NODE", element));34        }35    }36}...

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}...

ToStringTests.cs

Source:ToStringTests.cs

...11        }12        [Fact]13        public async Task ShouldWorkForPrimitives()14        {15            var numberHandle = await Page.EvaluateExpressionHandleAsync("2");16            Assert.Equal("JSHandle:2", numberHandle.ToString());17            var stringHandle = await Page.EvaluateExpressionHandleAsync("'a'");18            Assert.Equal("JSHandle:a", stringHandle.ToString());19        }20        [Fact]21        public async Task ShouldWorkForComplicatedObjects()22        {23            var aHandle = await Page.EvaluateExpressionHandleAsync("window");24            Assert.Equal("JSHandle@object", aHandle.ToString());25        }26    }27}...

MouseHelper.cs

Source:MouseHelper.cs

...11        public static async Task InstallMouseHelper(Page page)12        {13            var path = Path.Combine(Environment.CurrentDirectory, "GhostCursor", "follow-cursor.js"); 14            string jsContent = await File.ReadAllTextAsync(path);15            await page.EvaluateExpressionHandleAsync(jsContent);16        }17    }18}...

EvaluateExpressionHandleAsync

Using AI Code Generation

1var page = await browser.NewPageAsync();2await page.EvaluateExpressionHandleAsync("document");3await page.EvaluateExpressionHandleAsync("() => document");4var page = await browser.NewPageAsync();5await page.MainFrame.EvaluateExpressionHandleAsync("document");6await page.MainFrame.EvaluateExpressionHandleAsync("() => document");7var page = await browser.NewPageAsync();8var documentHandle = await page.EvaluateExpressionHandleAsync("document");9var bodyHandle = await page.EvaluateExpressionHandleAsync("() => document.body");10var htmlHandle = await page.EvaluateExpressionHandleAsync("() => document.documentElement");11var page = await browser.NewPageAsync();12var documentHandle = await page.EvaluateExpressionHandleAsync("document");13var bodyHandle = await page.EvaluateExpressionHandleAsync("() => document.body");14var htmlHandle = await page.EvaluateExpressionHandleAsync("() => document.documentElement");15var bodyHtmlHandle = await bodyHandle.EvaluateExpressionHandleAsync("() => document.documentElement");16var page = await browser.NewPageAsync();17var documentHandle = await page.EvaluateExpressionHandleAsync("document");18var bodyHandle = await page.EvaluateExpressionHandleAsync("() => document.body");19var htmlHandle = await page.EvaluateExpressionHandleAsync("() => document.documentElement");20var bodyHtmlHandle = await bodyHandle.EvaluateExpressionHandleAsync("() => document.documentElement");21var context = await page.GetContextAsync();22var bodyHtmlHandle2 = await context.EvaluateExpressionHandleAsync("() => document.documentElement");23var page = await browser.NewPageAsync();24var documentHandle = await page.EvaluateExpressionHandleAsync("

EvaluateExpressionHandleAsync

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 handle = await page.EvaluateExpressionHandleAsync("document");14            Console.WriteLine(await handle.JsonValueAsync());15            await browser.CloseAsync();16        }17    }18}19{20  "objectId": "{\"injectedScriptId\":3,\"id\":1}"21}

EvaluateExpressionHandleAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            var options = new LaunchOptions { Headless = false };9            var browser = await Puppeteer.LaunchAsync(options);10            var page = await browser.NewPageAsync();11            var expressionHandle = await page.EvaluateExpressionHandleAsync("document.body");12            var expression = await page.EvaluateFunctionAsync<string>("e => e.nodeName", expressionHandle);13            Console.WriteLine(expression);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 options = new LaunchOptions { Headless = false };26            var browser = await Puppeteer.LaunchAsync(options);27            var page = await browser.NewPageAsync();28            var expressionHandle = await page.EvaluateExpressionHandleAsync("document.body");29            var expression = await page.EvaluateFunctionAsync<string>("e => e.nodeName", expressionHandle);30            var body = expression;31            Console.WriteLine(body);32            await browser.CloseAsync();33        }34    }35}

EvaluateExpressionHandleAsync

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 result = await page.EvaluateExpressionHandleAsync("document.title");12            Console.WriteLine(result);13            await browser.CloseAsync();14        }15    }16}

EvaluateExpressionHandleAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            var options = new LaunchOptions { Headless = false };9            using (var browser = await Puppeteer.LaunchAsync(options))10            {11                var page = await browser.NewPageAsync();12                var result = await page.EvaluateExpressionHandleAsync<string>("2 + 2");13                Console.WriteLine(result.ToString());14                var result2 = await page.EvaluateExpressionHandleAsync<string>("await 2 + 2");15                Console.WriteLine(result2.ToString());16                var result3 = await page.EvaluateExpressionHandleAsync<string>("return await 2 + 2");17                Console.WriteLine(result3.ToString());18                var result4 = await page.EvaluateExpressionHandleAsync<string>("return await 2 + await 2");19                Console.WriteLine(result4.ToString());20                var result5 = await page.EvaluateExpressionHandleAsync<string>("var x = 2; return await x + await x");21                Console.WriteLine(result5.ToString());22                var result6 = await page.EvaluateExpressionHandleAsync<string>("var x = 2; var y = 2; return await x + await y");23                Console.WriteLine(result6.ToString());24                var result7 = await page.EvaluateExpressionHandleAsync<string>("var x = 2; var y = 2; return await x + await y + await z", new { z =

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