如何从 Microsoft.Toolkit WebView 中获取 HTML？

Question

I am using Microsoft.Toolkit.Forms.UI.Controls.WebView , available from https://www.nuget.org/packages/Microsoft.Toolkit.Forms.UI.Controls.WebView

我已将 WebView 添加到我的 WinForms 应用程序中 - 设计器代码：

namespace Testing
{
    partial class TestForm
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        { 
            this.pnlWebPage = new System.Windows.Forms.Panel();
            this.webView = new Microsoft.Toolkit.Forms.UI.Controls.WebView();
            this.pnlWebPage.SuspendLayout();
            ((System.ComponentModel.ISupportInitialize)(this.webView)).BeginInit();
            this.SuspendLayout();                            
            // 
            // pnlWebPage
            // 
            this.pnlWebPage.Controls.Add(this.webView);
            this.pnlWebPage.Dock = System.Windows.Forms.DockStyle.Fill;
            this.pnlWebPage.Location = new System.Drawing.Point(0, 101);
            this.pnlWebPage.Margin = new System.Windows.Forms.Padding(4);
            this.pnlWebPage.Name = "pnlWebPage";
            this.pnlWebPage.Size = new System.Drawing.Size(1205, 624);
            this.pnlWebPage.TabIndex = 3;
            // 
            // webView
            // 
            this.webView.Dock = System.Windows.Forms.DockStyle.Fill;
            this.webView.Location = new System.Drawing.Point(0, 0);
            this.webView.Margin = new System.Windows.Forms.Padding(4);
            this.webView.MinimumSize = new System.Drawing.Size(27, 25);
            this.webView.Name = "webView";
            this.webView.Size = new System.Drawing.Size(1205, 624);
            this.webView.Source = new System.Uri("https://www.bbc.com", System.UriKind.Absolute);
            this.webView.TabIndex = 0;
            this.webView.NavigationCompleted += new System.EventHandler<Microsoft.Toolkit.Win32.UI.Controls.Interop.WinRT.WebViewControlNavigationCompletedEventArgs>(this.webView_NavigationCompleted);
            // 
            // TestForm
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(8F, 16F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(1505, 725);
            this.Controls.Add(this.pnlWebPage);           
            this.Margin = new System.Windows.Forms.Padding(4);
            this.Name = "TestForm";
            this.Text = "TestForm";
            this.pnlWebPage.ResumeLayout(false);
            ((System.ComponentModel.ISupportInitialize)(this.webView)).EndInit();
            this.ResumeLayout(false);

        }

        #endregion

        private System.Windows.Forms.Panel pnlWebPage;
        private Microsoft.Toolkit.Forms.UI.Controls.WebView webView;
    }
}

一旦网站加载到 WebView 中，我希望能够提取页面的 HTML 并将其存储为字符串或类似内容。

我添加了以下方法，该方法在 WebView 的NavigationCompleted事件发生时调用。

private async void wvLI_NavigationCompleted(object sender, Microsoft.Toolkit.Win32.UI.Controls.Interop.WinRT.WebViewControlNavigationCompletedEventArgs e)
        {
           \\ HTML extraction to go here
}

但是，我看不到访问 HTML 的方法-似乎没有属性或类似的东西。 在研究如何执行此操作时，我只能找到与 Android 或 Xamarin 相关的问题和答案 - 这些解决方案都不适用于 Microsoft 工具包 WebView。 有谁知道我怎么能做到这一点？

Answer 1

您可以调用 JavaScript eval() function 通过调用InvokeScriptAsync （或InvokeScript ）来获取outerHTML （或innerHTML或任何你需要的），如下所示：

private async void wvLI_NavigationCompleted(object sender, Microsoft.Toolkit.Win32.UI.Controls.Interop.WinRT.WebViewControlNavigationCompletedEventArgs e)
{
     string html = await webView.InvokeScriptAsync("eval", new string[] { "document.documentElement.outerHTML;" });
}

重要的是，这发生在NavigationCompleted事件中，而不是DOMContentLoaded中，因为页面仅在NavigationCompleted触发时才完全加载