How to use ExposeFunctionAsync method of PuppeteerSharp.Page class
Best Puppeteer-sharp code snippet using PuppeteerSharp.Page.ExposeFunctionAsync
Window.cs
Source:Window.cs 
...63 public async Task CloseAsync()64 {65 await _page.CloseAsync();66 }67 public async Task ExposeFunctionAsync<TResult>(string name, Func<TResult> function)68 {69 await _page.ExposeFunctionAsync(name, function);70 }71 public async Task ExposeFunctionAsync<T, TResult>(string name, Func<T, TResult> function)72 {73 await _page.ExposeFunctionAsync(name, function);74 }75 public async Task ExposeFunctionAsync<T1, T2, TResult>(string name, Func<T1, T2, TResult> function)76 {77 await _page.ExposeFunctionAsync(name, function);78 }79 public async Task ExposeFunctionAsync<T1, T2, T3, TResult>(string name, Func<T1, T2, T3, TResult> function)80 {81 await _page.ExposeFunctionAsync(name, function);82 }83 public async Task ExposeFunctionAsync<T1, T2, T3, T4, TResult>(string name, Func<T1, T2, T3, T4, TResult> function)84 {85 await _page.ExposeFunctionAsync(name, function);86 }87 public async Task SendIpcMessageAsync(string channel, string message)88 {89 var script = $@"window.ipc.__receiveIpcMessage('{channel}', '{message}');";90 await EvaluateAsync(script);91 }92 public async Task SendIpcMessageAsync(string channel, JObject obj)93 {94 var script = $@"window.ipc.__receiveIpcMessage('{channel}', {obj});";95 await EvaluateAsync(script);96 }97 internal async Task InitAsync()98 {99 var targetId = _page.Target.TargetId;100 _session = await _page.Target.CreateCDPSessionAsync();101 var args = new JObject102 {103 { "expression", new JValue("self.paramsForReuse") },104 { "returnByValue", new JValue(true) }105 };106 var getParamsForReuseTask = _session.SendAsync("Runtime.evaluate", args);107 var targetObject = $"{{ targetId: '{targetId}' }}";108 var getWindowForTargetTask = _app.Session.SendAsync("Browser.getWindowForTarget", JObject.Parse(targetObject));109 var color = new JObject110 {111 { "color", new JObject112 {113 { "r", new JValue(_options.BgColor.R) },114 { "g", new JValue(_options.BgColor.G) },115 { "b", new JValue(_options.BgColor.B) },116 { "a", new JValue(_options.BgColor.A) },117 }118 }119 };120 await _session.SendAsync("Emulation.setDefaultBackgroundColorOverride", color);121 var response = await getParamsForReuseTask;122 _paramsForReuse = response.Value<object>();123 var window = await getWindowForTargetTask;124 await InitBoundsAsync(window);125 await ConfigureIpcMethodsOnceAsync();126 }127 private async Task ConfigureIpcMethodsOnceAsync()128 {129 if (!_ipcConfigured)130 {131 _ipcConfigured = true;132 await ExposeFunctionAsync<string, JToken, JToken>("__sendIpcMessageAsync", ReceiveIpcMessageAsync);133 await ExposeFunctionAsync<string, JToken, JToken>("__sendIpcMessageSync", ReceiveIpcMessageSync);134 } 135 }136 private async Task InitBoundsAsync(JObject result)137 {138 _windowId = result.Value<int>("windowId");139 var bounds = new JObject140 {141 { "top", _options.Top.GetValueOrDefault() },142 { "left", _options.Left.GetValueOrDefault() },143 { "width", _options.Width ?? 800 },144 { "height", _options.Height ?? 600 }145 };146 await SetBoundsAsync(bounds);147 }...
App.cs
Source:App.cs
...111 public void ServeAssembly(Assembly assembly, string @namespace, string prefix = "")112 {113 _www.Add(new ServingItem() { Prefix = WrapPrefix(prefix), Assembly = assembly, DefaultNamespace = @namespace });114 }115 public async Task ExposeFunctionAsync<T, TResult>(string name, Func<T, TResult> function)116 {117 _exposedFunctions.Add(name, function);118 var tasks = new List<Task>(_windows.Count);119 foreach (var window in _windows)120 {121 tasks.Add(window.ExposeFunctionAsync(name, function));122 }123 await Task.WhenAll(tasks.ToArray());124 }125 public async Task ExposeFunctionAsync<T>(string name, Func<T> function)126 {127 _exposedFunctions.Add(name, function);128 var tasks = new List<Task>(_windows.Count);129 foreach (var window in _windows)130 {131 tasks.Add(window.ExposeFunctionAsync(name, function));132 }133 await Task.WhenAll(tasks.ToArray());134 }135 public async Task SetIconAsync(string icon)136 {137 var buffer = File.ReadAllBytes(icon);138 var iconObject = new JObject()139 {140 { "image", Convert.ToBase64String(buffer) }141 };142 await _session.SendAsync("Browser.setDockTile", iconObject);143 }144 internal async Task InitAsync()145 {...
CaptchaControl.cs
Source:CaptchaControl.cs
...123 {*/124 /*using (*/ var page = await browser.NewPageAsync(); /*)125 {*/126 await page.GoToAsync(cbUrl.Text);127 await page.ExposeFunctionAsync("imgcl", async (string text) => 128 {129 Debug.WriteLine(text);130 await page.EvaluateExpressionAsync($"console.log('{text}')");131 //if (text.ToLower().Contains(args.TriggerWord) && !text.Contains(args.ResponseTemplate))132 //{133 // await RespondAsync(args, text);134 //}135 });136 //await Page.ExposeFunctionAsync("compute", (int a, int b) => a * b);137 // var result = await Page.EvaluateExpressionAsync<int>("compute(9, 4)");138 await page.EvaluateExpressionAsync("imgcl('ÑигнÑ')");139 await page.EvaluateExpressionAsync("imgcl('ÑигнÑ')");140 await page.EvaluateFunctionAsync(@"() => {141 let imgs = Array.from(document.querySelectorAll('img'));142 for (let i = 0; i < imgs.length; i++)143 {144 let a = imgs[i];145 console.log(`Binding for ${ a.src}`);146 // This event does not trigger!!!!!147 a.addEventListener('click', e => {148 console.log(`some one clicked the img ${e}`);149 imgcl('aaaaa');150 e.preventDefault();...
Program.cs
Source:Program.cs
...71 UserDataDir = UserDataDirPath(),72 DefaultViewport = null,73 });74 browserPage = (await browser.PagesAsync()).FirstOrDefault() ?? await browser.NewPageAsync();75 await browserPage.ExposeFunctionAsync("____callback____", (string returnValue) =>76 {77 callbackFromBrowserDelegate?.Invoke(returnValue);78 return 0;79 });80 }81 }82}...
HaxballApi.cs
Source:HaxballApi.cs
...61 .Map(handle => handle.RemoteObject.Value.ToString());62 }63 private async Task ExposeFunctions()64 {65 var exposePlayerJoined = Page.ExposeFunctionAsync<HaxballPlayer, object>("playerJoined", player => { ApiFunctions.OnPlayerJoin(player); return default!; });66 var exposeStartGame = Page.ExposeFunctionAsync<HaxballPlayer[], string[][], bool>("startGame", (players, idAuths) => ApiFunctions.StartGame(players.Select(player => player.EnrichAuth(idAuths)).ToArray()));67 var exposeFinishGame = Page.ExposeFunctionAsync<HaxballScores, bool>("finishGame", ApiFunctions.FinishGame);68 var exposeCloseRoom = Page.ExposeFunctionAsync("closeRoom", ApiFunctions.CloseRoom);69 var exposeSetStadium = Page.ExposeFunctionAsync<string, HaxballPlayer, object>("setStadium", (stadium, player) => { ApiFunctions.SetStadium(stadium, player); return default!; });70 var exposeHandleCommand = Page.ExposeFunctionAsync<HaxballPlayer, string, string>("handleCommand", ApiFunctions.HandleCommand);71 await Task.WhenAll(exposePlayerJoined, exposeStartGame, exposeFinishGame, exposeSetStadium, exposeHandleCommand);72 }73}...
test vueJS - Example1 - Refresh Top System Processes.csx
Source:test vueJS - Example1 - Refresh Top System Processes.csx
...5 public string Name {get; set; }6}7// found this example here: http://www.hardkoded.com/blog/creating-whatsapp-bot-puppteer-sharp8// documentation is here: https://www.puppeteersharp.com/api/PuppeteerSharp.Page.html9await page.ExposeFunctionAsync("sysCallGetTopProcesses", ()=>{10 var processes = Process.GetProcesses().Where(p=>{11 try{12 string name = p.ProcessName;13 var useTime = p.UserProcessorTime;14 return true;15 }catch(Exception ex){return false;}16 }).OrderBy(p=>p.UserProcessorTime.Ticks).Take(10);17 Console.WriteLine($"Found: {processes.Count()}");18 var result = processes.Select(p=> new ProcessInfo{19 Name = p.ProcessName20 }).ToList();21 return Newtonsoft.Json.Linq.JArray.FromObject(result);22});23/*...
ExposeFunctionTests.cs
Source:ExposeFunctionTests.cs
...11 }12 [Fact]13 public async Task ShouldWork()14 {15 await Page.ExposeFunctionAsync("compute", (int a, int b) => a * b);16 var result = await Page.EvaluateExpressionAsync<int>("compute(9, 4)");17 Assert.Equal(36, result);18 }19 [Fact]20 public async Task ShouldSurviveNavigation()21 {22 await Page.ExposeFunctionAsync("compute", (int a, int b) => a * b);23 await Page.GoToAsync(TestConstants.EmptyPage);24 var result = await Page.EvaluateExpressionAsync<int>("compute(9, 4)");25 Assert.Equal(36, result);26 }27 [Fact]28 public async Task ShouldAwaitReturnedValueTask()29 {30 await Page.ExposeFunctionAsync("compute", (int a, int b) => Task.FromResult(a * b));31 var result = await Page.EvaluateExpressionAsync<int>("compute(3, 5)");32 Assert.Equal(15, result);33 }34 [Fact]35 public async Task ShouldWorkOnFrames()36 {37 await Page.ExposeFunctionAsync("compute", (int a, int b) => Task.FromResult(a * b));38 await Page.GoToAsync(TestConstants.ServerUrl + "/frames/nested-frames.html");39 var frame = Page.Frames[1];40 var result = await frame.EvaluateExpressionAsync<int>("compute(3, 5)");41 Assert.Equal(15, result);42 }43 [Fact]44 public async Task ShouldWorkOnFramesBeforeNavigation()45 {46 await Page.GoToAsync(TestConstants.ServerUrl + "/frames/nested-frames.html");47 await Page.ExposeFunctionAsync("compute", (int a, int b) => Task.FromResult(a * b));48 var frame = Page.Frames[1];49 var result = await frame.EvaluateExpressionAsync<int>("compute(3, 5)");50 Assert.Equal(15, result);51 }52 [Fact]53 public async Task ShouldAwaitReturnedTask()54 {55 bool called = false;56 await Page.ExposeFunctionAsync("changeFlag", () =>57 {58 called = true;59 return Task.CompletedTask;60 });61 await Page.EvaluateExpressionAsync("changeFlag()");62 Assert.True(called);63 }64 [Fact]65 public async Task ShouldWorkWithAction()66 {67 bool called = false;68 await Page.ExposeFunctionAsync("changeFlag", () =>69 {70 called = true;71 });72 await Page.EvaluateExpressionAsync("changeFlag()");73 Assert.True(called);74 }75 }76}...
test vueJS.csx
Source:test vueJS.csx
...3using PuppeteerSharp;4var (page, browser) = await PuppeteerUtility.GetPage();5// found this example here: http://www.hardkoded.com/blog/creating-whatsapp-bot-puppteer-sharp6// documentation is here: https://www.puppeteersharp.com/api/PuppeteerSharp.Page.html7await page.ExposeFunctionAsync("funcTest1", ()=>{8 Console.WriteLine($"Function Test 1 Called");9});10/*11See vue.js documentation here:12https://vuejs.org/v2/guide/instance.html13*/14await page.SetContentAsync(html: @"15 <div id='displayDiv'>16 {{title}}17 <br />You've cliicked the button {{counter}} times.18 <br /><button type='button' v-on:click='onButton1Click'>Click Me!</button>19 <br /><button type='button' v-on:click='quit'>Quit</button>20 </div>21 <script type='module'>...
ExposeFunctionAsync
Using AI Code Generation
1var page = await browser.NewPageAsync();2await page.ExposeFunctionAsync("add", (int a, int b) => a + b);3var result = await page.EvaluateExpressionAsync<int>("add(5, 6)");4var page = await browser.NewPageAsync();5await page.ExposeFunctionAsync("add", (int a, int b) => a + b);6var result = await page.EvaluateExpressionAsync<int>("add(5, 6)");7var page = await browser.NewPageAsync();8await page.ExposeFunctionAsync("add", (int a, int b) => a + b);9var result = await page.EvaluateExpressionAsync<int>("add(5, 6)");10var page = await browser.NewPageAsync();11var result = await page.EvaluateExpressionAsync<int>("add(5, 6)");12await page.ExposeFunctionAsync("add", (int a, int b) => a + b);13var page = await browser.NewPageAsync();14await page.ExposeFunctionAsync("add", (int a, int b) => a + b);15await page.EvaluateExpressionAsync<int>("add(5, 6)");16var page = await browser.NewPageAsync();17await page.ExposeFunctionAsync("add", (int a, int b) => a + b);18await page.EvaluateExpressionAsync<int>("add(5, 6)");
ExposeFunctionAsync
Using AI Code Generation
1var page = await browser.NewPageAsync();2await page.ExposeFunctionAsync("add", (int a, int b) => a + b);3var result = await page.EvaluateFunctionAsync<int>("async () => add(5, 6)");4var page = await browser.NewPageAsync();5var frame = page.MainFrame;6await frame.ExposeFunctionAsync("add", (int a, int b) => a + b);7var result = await frame.EvaluateFunctionAsync<int>("async () => add(5, 6)");8var page = await browser.NewPageAsync();9var elementHandle = await page.QuerySelectorAsync("input");10await elementHandle.ExposeFunctionAsync("add", (int a, int b) => a + b);11var result = await elementHandle.EvaluateFunctionAsync<int>("async () => add(5, 6)");12using (var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = true }))13{14 var page = await browser.NewPageAsync();15 await page.ExposeFunctionAsync("add", (int a, int b) => a + b);16 var result = await page.EvaluateFunctionAsync<int>("async () => add(5, 6)");17}18using (var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = true }))19{20 var page = await browser.NewPageAsync();21 var frame = page.MainFrame;22 await frame.ExposeFunctionAsync("add", (int a, int b) => a + b);23 var result = await frame.EvaluateFunctionAsync<int>("async () => add(5, 6)");24}25using (var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = true }))26{27 var page = await browser.NewPageAsync();28 var elementHandle = await page.QuerySelectorAsync("input");
ExposeFunctionAsync
Using AI Code Generation
1var page = await browser.NewPageAsync();2await page.ExposeFunctionAsync("add", (int a, int b) => a + b);3var result = await page.EvaluateExpressionAsync<int>("add(5, 6)");4var page = await browser.NewPageAsync();5var frame = await page.GetMainFrameAsync();6await frame.ExposeFunctionAsync("add", (int a, int b) => a + b);7var result = await page.EvaluateExpressionAsync<int>("add(5, 6)");8var page = await browser.NewPageAsync();9await page.ExposeFunctionAsync("add", (int a, int b) => a + b);10var result = await page.EvaluateFunctionAsync<int>("add", 5, 6);11var page = await browser.NewPageAsync();12var frame = await page.GetMainFrameAsync();13await frame.ExposeFunctionAsync("add", (int a, int b) => a + b);14var result = await page.EvaluateFunctionAsync<int>("add", 5, 6);15var page = await browser.NewPageAsync();16await page.ExposeFunctionAsync("add", (int a, int b) => a + b);17var result = await page.EvaluateFunctionHandleAsync<int>("add", 5, 6);18var page = await browser.NewPageAsync();19var frame = await page.GetMainFrameAsync();20await frame.ExposeFunctionAsync("add", (int a,
ExposeFunctionAsync
Using AI Code Generation
1await page.ExposeFunctionAsync("sum", (int a, int b) => a + b);2await page.ExposeFunctionAsync("sum", (int a, int b) => a + b);3await page.ExposeFunctionAsync("sum", (int a, int b) => a + b);4await page.ExposeFunctionAsync("sum", (int a, int b) => a + b);5await page.ExposeFunctionAsync("sum", (int a, int b) => a + b);6await page.ExposeFunctionAsync("sum", (int a, int b) => a + b);7await page.ExposeFunctionAsync("sum", (int a, int b) => a + b);8await page.ExposeFunctionAsync("sum", (int a, int b) => a + b);
ExposeFunctionAsync
Using AI Code Generation
1{2 static void Main(string[] args)3 {4 MainAsync(args).GetAwaiter().GetResult();5 }6 static async Task MainAsync(string[] args)7 {8 var browser = await Puppeteer.LaunchAsync(new LaunchOptions9 {10 });11 var page = await browser.NewPageAsync();12 await page.ExposeFunctionAsync("add", (Func<int, int, int>)((x, y) => x + y));13 var result = await page.EvaluateExpressionAsync<int>("add(5, 6)");14 Console.WriteLine(result);15 await browser.CloseAsync();16 }17}18{19 static void Main(string[] args)20 {21 MainAsync(args).GetAwaiter().GetResult();22 }23 static async Task MainAsync(string[] args)24 {25 var browser = await Puppeteer.LaunchAsync(new LaunchOptions26 {27 });28 var page = await browser.NewPageAsync();29 await page.ExposeFunctionAsync("add", (Func<int, int, int>)((x, y) => x + y));30 var result = await page.EvaluateExpressionAsync<int>("add(5, 6)");31 Console.WriteLine(result);32 await browser.CloseAsync();33 }34}35{36 static void Main(string[] args)37 {38 MainAsync(args).GetAwaiter().GetResult();39 }40 static async Task MainAsync(string[] args)41 {42 var browser = await Puppeteer.LaunchAsync(new LaunchOptions43 {44 });45 var page = await browser.NewPageAsync();46 await page.ExposeFunctionAsync("add", (Func<int, int, int>)((x, y) => x + y));47 var result = await page.EvaluateExpressionAsync<int>("add(5, 6)");48 Console.WriteLine(result);
ExposeFunctionAsync
Using AI Code Generation
1page.ExposeFunctionAsync("myFunction", async (int arg1, string arg2) =>2{3 return arg1.ToString() + arg2;4});5var result = await page.EvaluateFunctionAsync<string>("(arg1, arg2) => { return myFunction(arg1, arg2); }", 1, "2");6page.ExposeFunctionAsync("myFunction", async (int arg1, string arg2) =>7{8 return arg1.ToString() + arg2;9});10var result = await page.EvaluateExpressionAsync<string>("myFunction(1, '2')");11page.ExposeFunctionAsync("myFunction", async (int arg1, string arg2) =>12{13 return arg1.ToString() + arg2;14});15var result = await page.EvaluateFunctionAsync<string>("() => { return myFunction(1, '2'); }");
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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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