How to use WaitForExpressionAsync method of PuppeteerSharp.Page class
Best Puppeteer-sharp code snippet using PuppeteerSharp.Page.WaitForExpressionAsync
WebScraper.cs
Source:WebScraper.cs 
...238 WaitOnScriptAsync(expression).Wait();239 }240 private async Task WaitOnScriptAsync(string expression)241 {242 await m_page.WaitForExpressionAsync(expression);243 }244 /// <summary>245 /// Selects element on page to have focus.246 /// </summary>247 /// <param name="target">Javascript selector to make have focus.</param>248 public void Focus(string target)249 {250 FocusAsync(target).Wait();251 }252 private async Task FocusAsync(string target)253 {254 await m_page.FocusAsync(target);255 }256 /// <summary>...
Program.cs
Source:Program.cs
...52 });53 await RacePageUtils.AcceptEverything();54 await RacePageUtils.LaunchRace();55 56 await Page.WaitForExpressionAsync(57 "document.querySelector('#inputtextblock #inputtext').disabled===false",58 new WaitForFunctionOptions() { Timeout = 666666 }59 );60 await Page.WaitForTimeoutAsync(300);61 var text = await Page.EvaluateExpressionAsync<string>("document.querySelector('#typetext').innerText");62 #region Detect alphabet and game mode63 bool isCyrillicMode = isCyrillicRgx.IsMatch(text);64 var gameTypeExp = "document.querySelector('#gamedesc').innerText.split(',')[0]";65 var gameType = await Page.EvaluateExpressionAsync<string>(gameTypeExp);66 gameType = gameType.Trim().TrimStart('«').TrimEnd('»');67 var noErrorMode = gameType == "ÐезоÑибоÑнÑй";68 #endregion69 await Page.FocusAsync("#inputtextblock #inputtext");70 foreach (char c in text)...
PuppeteerBannerGenerator.cs
Source:PuppeteerBannerGenerator.cs
...38 await StartBrowserAsync();39 using var page = await _browser.NewPageAsync();40 await page.GoToAsync("https://localhost:5001/erikolsson.html?identifier=" + identifier);41 // Wait for window.documentReady to be set to true (needs to be handled by the page after all images have loaded)42 await page.WaitForExpressionAsync("window.documentReady === true", new WaitForFunctionOptions { Polling = WaitForFunctionPollingOption.Raf });43 // Puppeteer starts with a too small viewport so we need to resize it44 await page.SetViewportAsync(new ViewPortOptions { Width = 1500, Height = 1500 });45 // Get the main element and create a PNG screenshot of it46 var mainElement = await page.QuerySelectorAsync("main");47 using var screenshotStream = await mainElement.ScreenshotStreamAsync(new ScreenshotOptions { Type = ScreenshotType.Png });48 using var ms = new MemoryStream();49 await screenshotStream.CopyToAsync(ms, cancellationToken);50 return ms.ToArray().AsMemory();51 }52 public async ValueTask DisposeAsync() {53 if(_browser != null) {54 await _browser.DisposeAsync();55 }56 }...
test vueJS - Example1 - Refresh Top System Processes.csx
Source:test vueJS - Example1 - Refresh Top System Processes.csx
...76 ()=> {77 window.programDone = false;78 }79 ");80 await page.WaitForExpressionAsync("window.programDone === true", new WaitForFunctionOptions{81 Timeout = 0 // disable the timeout82 });83 Console.WriteLine("Program finished triggered");84 // program is done so close everything out85 await page.CloseAsync();86 await browser.CloseAsync();87}88await waitForProgramEnd();...
SearchPage.cs
Source:SearchPage.cs
...16[0]17";18 static async Task WaitForSearchResultCount(Page page)19 {20 await page.WaitForExpressionAsync(SearchResultCount);21 }22 static async Task<int?> GetSearchResultCount(Page page)23 {24 return await page.EvaluateExpressionAsync<int?>(SearchResultCount);25 }26 public static async Task ClickSearchButton(Page page)27 {28 await page.ClickAsync(".btn.btn-lg.btn-primary.track-event");29 }30 public static async Task WaitForFilledAndSubmittedSearchPage(Page page)31 {32 while (true)33 {34 try35 {36 if (await GetSearchResultCount(page) != null) break;37 }38 catch (PuppeteerException) { }39 await Task.Delay(1000);40 }41 }42 public static async Task WaitForFirstPageLoad(Page page)43 {44 var script = @"document.querySelector(""[src^='/assets/looading-gif']"") == null";45 await page.WaitForExpressionAsync(script);46 await WaitForSearchResultCount(page);47 var count = await GetSearchResultCount(page);48 if (count == 0) return;49 await page.WaitForExpressionAsync("document.querySelector('.lazy-load-image') == null");50 }51 public static async Task<bool> CanGoToNextPage(Page page)52 {53 await WaitForFirstPageLoad(page);54 const string script = @"(() => document.querySelector('.btn.btn-default.btn-lg') !== null )()";55 var result = await page.EvaluateExpressionAsync<bool>(script);56 return result;57 }58 public static async Task GoToNextPage(Page page)59 {60 await page.WaitForSelectorAsync(".btn.btn-default.btn-lg");61 try62 {63 await page.EvaluateExpressionAsync("document.querySelector('.btn.btn-default.btn-lg').click()");...
ScreenshotService.cs
Source:ScreenshotService.cs
...36 }37 var browser = await GetBrowser();38 var page = await browser.NewPageAsync();39 await page.GoToAsync(uri);40 await page.WaitForExpressionAsync("arma3TacMapLoaded", new WaitForFunctionOptions() { PollingInterval = 500, Timeout = 7500 });41 var bytes = await page.ScreenshotDataAsync();42 await page.CloseAsync();43 return bytes;44 }45 private async Task<Browser> GetBrowser()46 {47 if (browserTask == null)48 {49 await semaphoreSlim.WaitAsync();50 try51 {52 if (browserTask == null)53 {54 browserTask = GetBrowserTask();...
test vueJS.csx
Source:test vueJS.csx
...55 ()=> {56 window.programDone = false;57 }58 ");59 await page.WaitForExpressionAsync("window.programDone === true", new WaitForFunctionOptions{60 Timeout = 0 // disable timeout61 });62 Console.WriteLine("Program finished triggered");63 // program is done so close everything out64 await page.CloseAsync();65 await browser.CloseAsync();66}67await waitForProgramEnd();...
PuppeteerExtensions.cs
Source:PuppeteerExtensions.cs
...24 await (await frame.QuerySelectorAsync(selector)).ClickAsync();25 }26 public static async Task WaitForTruth(this Page page, string script, WaitForFunctionOptions opts = null)27 {28 var jsHandle = await page.WaitForExpressionAsync(script, opts);29 await jsHandle.DisposeAsync();30 }31 public static async Task WaitForDocumentInteractiveState(this Page page, int? timeout = null)32 {33 await page.WaitForTruth("document.readyState === 'interactive' || document.readyState === 'complete'", new WaitForFunctionOptions { Timeout = timeout ?? page.Browser.DefaultWaitForTimeout });34 }35 }36}
WaitForExpressionAsync
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, SlowMo = 50 };9 var browser = await Puppeteer.LaunchAsync(options);10 var page = await browser.NewPageAsync();11 await page.WaitForSelectorAsync("input[title='Search']");12 await page.TypeAsync("input[title='Search']", "PuppeteerSharp");13 await page.Keyboard.PressAsync("Enter");14 await page.WaitForNavigationAsync();15 await page.WaitForExpressionAsync("document.querySelector('h3').textContent.includes('PuppeteerSharp')");16 Console.WriteLine("PuppeteerSharp is found!");17 await browser.CloseAsync();18 }19 }20}
WaitForExpressionAsync
Using AI Code Generation
1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5 {6 static async Task Main(string[] args)7 {8 {9 Args = new string[] { "--no-sandbox" }10 };11 using (var browser = await Puppeteer.LaunchAsync(options))12 using (var page = await browser.NewPageAsync())13 {14 await page.WaitForExpressionAsync("document.querySelector('input[name=q]').value == 'puppeteer'");15 Console.WriteLine("Page loaded");16 }17 }18 }19}
WaitForExpressionAsync
Using AI Code Generation
1var browser = await Puppeteer.LaunchAsync(new LaunchOptions2{3});4var page = await browser.NewPageAsync();5await page.WaitForExpressionAsync("document.querySelector('input[name=q]').value");6await browser.CloseAsync();7var browser = await Puppeteer.LaunchAsync(new LaunchOptions8{9});10var page = await browser.NewPageAsync();11await page.WaitForSelectorAsync("input[name=q]");12await browser.CloseAsync();13var browser = await Puppeteer.LaunchAsync(new LaunchOptions14{15});16var page = await browser.NewPageAsync();17await page.WaitForFunctionAsync("document.querySelector('input[name=q]').value");18await browser.CloseAsync();19var browser = await Puppeteer.LaunchAsync(new LaunchOptions20{21});22var page = await browser.NewPageAsync();23await page.WaitForNavigationAsync();24await browser.CloseAsync();25var browser = await Puppeteer.LaunchAsync(new LaunchOptions26{27});28var page = await browser.NewPageAsync();29await browser.CloseAsync();30var browser = await Puppeteer.LaunchAsync(new LaunchOptions31{32});
WaitForExpressionAsync
Using AI Code Generation
1var browser = await Puppeteer.LaunchAsync(new LaunchOptions2{3});4var page = await browser.NewPageAsync();5var result = await page.WaitForExpressionAsync("document.querySelector('input') != null");6if (result)7{8 Console.WriteLine("WaitForExpressionAsync succeeded");9}10{11 Console.WriteLine("WaitForExpressionAsync failed");12}13await page.CloseAsync();14await browser.CloseAsync();15var browser = await Puppeteer.LaunchAsync(new LaunchOptions16{17});18var page = await browser.NewPageAsync();19var result = await page.WaitForFunctionAsync("document.querySelector('input') != null");20if (result)21{22 Console.WriteLine("WaitForFunctionAsync succeeded");23}24{25 Console.WriteLine("WaitForFunctionAsync failed");26}27await page.CloseAsync();28await browser.CloseAsync();29var browser = await Puppeteer.LaunchAsync(new LaunchOptions30{31});32var page = await browser.NewPageAsync();33var response = await page.WaitForNavigationAsync();34if (response != null)35{36 Console.WriteLine("WaitForNavigationAsync succeeded");37}38{39 Console.WriteLine("WaitForNavigationAsync failed");40}41await page.CloseAsync();42await browser.CloseAsync();43var browser = await Puppeteer.LaunchAsync(new LaunchOptions44{45});46var page = await browser.NewPageAsync();47if (request != null)48{49 Console.WriteLine("WaitForRequestAsync succeeded");50}51{52 Console.WriteLine("WaitForRequestAsync failed
WaitForExpressionAsync
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 using (var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = false }))10 using (var page = await browser.NewPageAsync())11 {12 await page.WaitForExpressionAsync("document.querySelector('input[name=\"q\"]').value == 'puppeteer'");13 }14 }15 }16}17using System;18using System.Threading.Tasks;19using PuppeteerSharp;20{21 {22 static async Task Main(string[] args)23 {24 await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);25 using (var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = false }))26 using (var page = await browser.NewPageAsync())27 {28 await page.WaitForFunctionAsync("document.querySelector('input[name=\"q\"]').value == 'puppeteer'");29 }30 }31 }32}33using System;34using System.Threading.Tasks;35using PuppeteerSharp;36{37 {38 static async Task Main(string[] args)39 {40 await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);41 using (var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = false }))42 using (var page = await browser.NewPageAsync())43 {44 await page.WaitForSelectorAsync("input[name=\"q\"]");45 }46 }47 }48}
WaitForExpressionAsync
Using AI Code Generation
1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5 {6 public static async Task<string> Run()7 {8 var browser = await Puppeteer.LaunchAsync(new LaunchOptions9 {10 });11 var page = await browser.NewPageAsync();12 var result = await page.WaitForExpressionAsync("window.innerWidth < 100");13 var result2 = await page.WaitForExpressionAsync("window.innerWidth < 100", new WaitForOptions14 {15 });16 var result3 = await page.WaitForExpressionAsync(() => page.EvaluateFunctionAsync("() => window.innerWidth < 100"), new WaitForOptions17 {18 });19 await browser.CloseAsync();20 return "ok";21 }22 }23}
WaitForExpressionAsync
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 await page.WaitForNavigationAsync();13 await page.WaitForExpressionAsync("document.readyState === 'complete'");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 await page.WaitForNavigationAsync();
WaitForExpressionAsync
Using AI Code Generation
1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5 {6 public 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 await page.WaitForExpressionAsync("x == 5");14 Console.WriteLine("x is 5");15 await browser.CloseAsync();16 }17 }18}19using System;20using System.Threading.Tasks;21using PuppeteerSharp;22{23 {24 public 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 await page.WaitForFunctionAsync("x == 5");32 Console.WriteLine("x is 5");33 await browser.CloseAsync();34 }35 }36}37using System;38using System.Threading.Tasks;39using PuppeteerSharp;40{41 {42 public static async Task Main(string[] args)43 {44 await new BrowserFetcher().DownloadAsync(BrowserFetcher.Default
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Most used method in Page
- FrameManagerGetFrames
- workersValuesToArray
- PopupGetInvocationList
- clientDisconnected
- SetGeolocationAsync
- SetDragInterceptionAsync
- MetricsAsync
- TapAsync
- QuerySelectorAsync
- QuerySelectorAllAsync
- QuerySelectorAllHandleAsync
- XPathAsync
- EvaluateExpressionHandleAsync
- EvaluateFunctionHandleAsync
- EvaluateOnNewDocumentAsync
- EvaluateFunctionOnNewDocumentAsync
- EvaluateExpressionOnNewDocumentAsync
- QueryObjectsAsync
- SetRequestInterceptionAsync
- SetOfflineModeAsync
- EmulateNetworkConditionsAsync
- GetCookiesAsync
- SetCookieAsync
- DeleteCookieAsync
- AddScriptTagAsync
- AddStyleTagAsync
- ExposeFunctionAsync
- TResult
- GetContentAsync
- SetContentAsync
- GoToAsync
- PdfAsync
- PdfStreamAsync
- PdfDataAsync
- SetJavaScriptEnabledAsync
- SetBypassCSPAsync
- EmulateMediaAsync
- EmulateMediaTypeAsync
- EmulateMediaFeaturesAsync
- SetViewportAsync
- EmulateAsync
- ScreenshotAsync
- ScreenshotStreamAsync
- ScreenshotBase64Async
- ScreenshotDataAsync
- GetTitleAsync
- CloseAsync
- SetCacheEnabledAsync
- ClickAsync
- HoverAsync
- FocusAsync
- TypeAsync
- EvaluateExpressionAsync
- EvaluateFunctionAsync
- SetUserAgentAsync
- SetExtraHttpHeadersAsync
- AuthenticateAsync
- ReloadAsync
- SelectAsync
- WaitForTimeoutAsync
- WaitForFunctionAsync
- WaitForExpressionAsync
- WaitForSelectorAsync
- WaitForXPathAsync
- WaitForNavigationAsync
- WaitForNetworkIdleAsync
- Evaluate
- requestEventListener
- responseEventListener
- Cleanup
- WaitForRequestAsync
- WaitForResponseAsync
- WaitForFileChooserAsync
- GoBackAsync
- GoForwardAsync
- SetBurstModeOffAsync
- BringToFrontAsync
- EmulateVisionDeficiencyAsync
- EmulateTimezoneAsync
- EmulateIdleStateAsync
- EmulateCPUThrottlingAsync
- OnPopup
- InitializeAsync
- GoAsync
- ClientMessageReceived
- OnDetachedFromTarget
- OnTargetCrashed
- EmitMetrics
- HandleException
- OnDialog
- Dispose
- DisposeAsync
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