C# WebBrowser 控件 - 使用 InvokeMember("Click") 提交表单不起作用

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【中文标题】C# WebBrowser 控件 - 使用 InvokeMember("Click") 提交表单不起作用【英文标题】:C# WebBrowser Control - Form Submit Not Working using InvokeMember("Click") 【发布时间】:2013-10-03 09:22:49 【问题描述】:

我正在编写自动化测试脚本并使用 WebBrowser 控件。当用户接受服务条款时,我正在尝试提交以下 html 并进行测试:

    <form action="http://post.dev.dealerconnextion/k/6hRbDTwn4xGVl2MHITQsBw/hrshq" method="post">
        <input name="StepCheck" value="U2FsdGVkX18zMTk5MzE5OUgFyFgD3V5yf5Rwbtfhf3gjdH4KSx4hqj4vkrw7K6e-" type="hidden">
        <button type="submit" name="continue" value="y">ACCEPT the terms of use</button>
        <button type="submit" name="continue" value="n">DECLINE the terms of use</button>
    </form>

    // Terms of Use Information

    <form action="http://post.dev.dealerconnextion/k/6hRbDTwn4xGVl2MHITQsBw/hrshq" method="post">
        <input name="StepCheck" value="U2FsdGVkX18zMTk5MzE5OUgFyFgD3V5yf5Rwbtfhf3gjdH4KSx4hqj4vkrw7K6e-" type="hidden">
        <button type="submit" name="continue" value="y">ACCEPT the terms of use</button>
        <button type="submit" name="continue" value="n">DECLINE the terms of use</button>
    </form>

这里是 C# 中的代码,但没有提交表单。

            HtmlElementCollection el = webBrowser.Document.GetElementsByTagName("button");
            foreach (HtmlElement btn in el)
            
                if (btn.InnerText == "ACCEPT the terms of use")
                
                    btn.InvokeMember("Click");
                
            

任何帮助将不胜感激。谢谢。

【问题讨论】:

您应该在发生DocumentCompleted 事件时致电btn.InvokeMember("Click")。如果这就是你所做的,并且你在该行上放置了一个断点,它会在调试器中被命中吗? 我确实添加了一个 DocumentCompleted 事件。是的, btn.InvokeMember("Click") 确实在调试器中被击中。只是什么都没发生。 当从DocumentComplete 调用时,您的代码适用于我(使用自定义本地操作 URL)。 你能告诉我你正在使用的代码 - 只是为了清楚 - 谢谢 代码很简单:pastebin.com/M08bxjwP。 test.html 包含从您的问题复制的 HTML(除了 URL)。 【参考方案1】:

以下代码适用于我,使用问题 cmets 中的实时表单操作 URL,并使用 IE10 进行了测试。按原样尝试。如果它也适用于您,请随意将其用作您的 Web 自动化任务的模板。几点:

FEATURE_BROWSER_EMULATION 用于确保WebBrowser 的行为方式与独立 IE 浏览器相同(或尽可能接近)。 这对于几乎所有基于WebBrowser 的项目来说都是必须的。我相信这应该有助于解决您的原始问题。

异步代码用于提高自动化逻辑可靠性,添加支持超时和取消,促进自然的线性代码流(使用async/await)。

C#

using Microsoft.Win32;
using System;
using System.Diagnostics;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WebAutomation

    // http://***.com/q/19044659/1768303

    public partial class MainForm : Form
    
        WebBrowser webBrowser;

        // non-deterministic delay to let AJAX code run
        const int AJAX_DELAY = 1000;

        // keep track of the main automation task
        CancellationTokenSource mainCts;
        Task mainTask = null;

        public MainForm()
        
            SetBrowserFeatureControl(); // set FEATURE_BROWSER_EMULATION first

            InitializeComponent();

            InitBrowser();

            this.Load += (s, e) =>
            
                // start the automation when form is loaded
                // timeout the whole automation task in 30s
                mainCts = new CancellationTokenSource(30000);
                mainTask = DoAutomationAsync(mainCts.Token).ContinueWith((completedTask) =>
                
                    Trace.WriteLine(String.Format("Automation task status: 0", completedTask.Status.ToString()));
                , TaskScheduler.FromCurrentSynchronizationContext());
            ;

            this.FormClosing += (s, e) =>
            
                // cancel the automation if form closes
                if (this.mainTask != null && !this.mainTask.IsCompleted)
                    mainCts.Cancel();
            ;
        

        // create a WebBrowser instance (could use an existing one)
        void InitBrowser()
        
            this.webBrowser = new WebBrowser();
            this.webBrowser.Dock = DockStyle.Fill;
            this.Controls.Add(this.webBrowser);
            this.webBrowser.Visible = true;
        

        // the main automation logic
        async Task DoAutomationAsync(CancellationToken ct)
        
            await NavigateAsync(ct, () => this.webBrowser.Navigate("http://localhost:81/test.html"), 10000); // timeout in 10s
            // page loaded, log the page's HTML
            Trace.WriteLine(GetBrowserDocumentHtml());

            // do the DOM automation
            HtmlElementCollection all = webBrowser.Document.GetElementsByTagName("button");
            // throw if none or more than one element found
            HtmlElement btn = all.Cast<HtmlElement>().Single(
                el => el.InnerHtml == "ACCEPT the terms of use");

            ct.ThrowIfCancellationRequested();

            // simulate a click which causes navigation
            await NavigateAsync(ct, () => btn.InvokeMember("click"), 10000); // timeout in 10s

            // form submitted and new page loaded, log the page's HTML
            Trace.WriteLine(GetBrowserDocumentHtml());

            // could continue with another NavigateAsync
            // othrwise, the automation session completed
        

        // Get the full HTML content of the document
        string GetBrowserDocumentHtml()
        
            return this.webBrowser.Document.GetElementsByTagName("html")[0].OuterHtml;
        

        // Async navigation
        async Task NavigateAsync(CancellationToken ct, Action startNavigation, int timeout = Timeout.Infinite)
        
            var onloadTcs = new TaskCompletionSource<bool>();
            EventHandler onloadEventHandler = null;

            WebBrowserDocumentCompletedEventHandler documentCompletedHandler = delegate
            
                // DocumentCompleted may be called several time for the same page,
                // beacuse of frames
                if (onloadEventHandler != null || onloadTcs == null || onloadTcs.Task.IsCompleted)
                    return;

                // handle DOM onload event to make sure the document is fully loaded
                onloadEventHandler = (s, e) =>
                    onloadTcs.TrySetResult(true);
                this.webBrowser.Document.Window.AttachEventHandler("onload", onloadEventHandler);
            ;

            using (var cts = CancellationTokenSource.CreateLinkedTokenSource(ct))
            
                if (timeout != Timeout.Infinite)
                    cts.CancelAfter(Timeout.Infinite);

                using (cts.Token.Register(() => onloadTcs.TrySetCanceled(), useSynchronizationContext: true)) 
                
                    this.webBrowser.DocumentCompleted += documentCompletedHandler;
                    try 
                    
                        startNavigation();
                        // wait for DOM onload, throw if cancelled
                        await onloadTcs.Task;
                        ct.ThrowIfCancellationRequested();
                        // let AJAX code run, throw if cancelled
                        await Task.Delay(AJAX_DELAY, ct);
                    
                    finally 
                    
                        this.webBrowser.DocumentCompleted -= documentCompletedHandler;
                        if (onloadEventHandler != null)
                            this.webBrowser.Document.Window.DetachEventHandler("onload", onloadEventHandler);
                    
                
            
        

        // Browser feature conntrol
        void SetBrowserFeatureControl()
        
            // http://msdn.microsoft.com/en-us/library/ee330720(v=vs.85).aspx

            // FeatureControl settings are per-process
            var fileName = System.IO.Path.GetFileName(Process.GetCurrentProcess().MainModule.FileName);

            // make the control is not running inside Visual Studio Designer
            if (String.Compare(fileName, "devenv.exe", true) == 0 || String.Compare(fileName, "XDesProc.exe", true) == 0)
                return;

            SetBrowserFeatureControlKey("FEATURE_BROWSER_EMULATION", fileName, GetBrowserEmulationMode()); // Webpages containing standards-based !DOCTYPE directives are displayed in IE10 Standards mode.
        

        void SetBrowserFeatureControlKey(string feature, string appName, uint value)
        
            using (var key = Registry.CurrentUser.CreateSubKey(
                String.Concat(@"Software\Microsoft\Internet Explorer\Main\FeatureControl\", feature),
                RegistryKeyPermissionCheck.ReadWriteSubTree))
            
                key.SetValue(appName, (UInt32)value, RegistryValueKind.DWord);
            
        

        UInt32 GetBrowserEmulationMode()
        
            int browserVersion = 7;
            using (var ieKey = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\Internet Explorer",
                RegistryKeyPermissionCheck.ReadSubTree,
                System.Security.AccessControl.RegistryRights.QueryValues))
            
                var version = ieKey.GetValue("svcVersion");
                if (null == version)
                
                    version = ieKey.GetValue("Version");
                    if (null == version)
                        throw new ApplicationException("Microsoft Internet Explorer is required!");
                
                int.TryParse(version.ToString().Split('.')[0], out browserVersion);
            

            UInt32 mode = 10000; // Internet Explorer 10. Webpages containing standards-based !DOCTYPE directives are displayed in IE10 Standards mode. Default value for Internet Explorer 10.
            switch (browserVersion)
            
                case 7:
                    mode = 7000; // Webpages containing standards-based !DOCTYPE directives are displayed in IE7 Standards mode. Default value for applications hosting the WebBrowser Control.
                    break;
                case 8:
                    mode = 8000; // Webpages containing standards-based !DOCTYPE directives are displayed in IE8 mode. Default value for Internet Explorer 8
                    break;
                case 9:
                    mode = 9000; // Internet Explorer 9. Webpages containing standards-based !DOCTYPE directives are displayed in IE9 mode. Default value for Internet Explorer 9.
                    break;
                default:
                    // use IE10 mode by default
                    break;
            

            return mode;
        
    

http://localhost:81/test.html的内容:

<!DOCTYPE html>
<head>
<meta http-equiv="X-UA-Compatible" content="IE=edge"/>
</head>
<body>
    <form action="<the URL from OP's comments>" method="post">
        <input name="StepCheck" value="U2FsdGVkX18zMTk5MzE5OUgFyFgD3V5yf5Rwbtfhf3gjdH4KSx4hqj4vkrw7K6e-" type="hidden">
        <button type="submit" name="continue" value="y">ACCEPT the terms of use</button>
        <button type="submit" name="continue" value="n">DECLINE the terms of use</button>
    </form>
</body>

【讨论】:

请问this.FormClosing += (s, e) =&gt; 的代码是做什么的?谢谢。 @Sabuncu,它处理FormClosing 事件以取消任何挂起的后台导航操作。 @Noseratio 解决方案是如此晦涩难懂,以至于我需要很长时间才能找到。我的支持和感谢 =) 请问HTML表单标签是否包含相对路径代码不起作用?有什么问题吗?你能提供这个问题的答案吗:***.com/questions/69567116/… @Hardik 无法回答这个问题,但你得到的答案/cmets 很好。你真的应该在 2021 年使用 WebView2 和 IE11 WebBrowser【参考方案2】:

这对我有用,如下所示。可能对某人有用。

首先,我在获得焦点时为按钮元素创建一个事件处理程序。一旦所有其他表单元素都填充了适当的值,您应该将焦点放在按钮上,如下所示:

HtmlElement xUsername = xDoc.GetElementById("username_txt");
HtmlElement xPassword = xDoc.GetElementById("password_txt");
HtmlElement btnSubmit = xDoc.GetElementById("btnSubmit");
if (xUsername != null && xPassword != null && btnSubmit != null)

    xUsername.SetAttribute("value", "testUserName");
    xPassword.SetAttribute("value", "123456789");
    btnSubmit.GotFocus += BtnSubmit_GotFocus;
    btnSubmit.Focus();

那么事件处理程序的实现会是这样的:

private void BtnSubmit_GotFocus(object sender, HtmlElementEventArgs e)

    var btnSubmit = sender as HtmlElement;
    btnSubmit.RaiseEvent("onclick");
    btnSubmit.InvokeMember("click");

【讨论】:

【参考方案3】:

在我的情况下,我也无法通过简单地调用找到的元素的 Click 方法来点击元素。 有效的是 Ali Tabandeh 在上面的答案中列出的类似解决方案:

    找到需要的html元素 定义适当的 GotFocus 事件处理程序 然后调用找到的元素的 Focus 方法。

GotFocus 的事件处理程序应该

    RaiseEvent“点击” 调用“点击”方法

问题是这在我的情况下从第三次开始(调用 htmlelement.Focus() 需要 3 次)。

【讨论】:

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