Web 浏览器控件加载完成

Question

我在我的表单中使用 Web 浏览器，它可以导航到多个页面。我想在完全加载后截取最后一页的屏幕截图。我已经编写了在webBrowser1_DocumentCompleted内截屏的代码。但是，它会在加载页面之前截取屏幕截图。我很困惑在哪里可以截取屏幕截图。我在谷歌中找到了加载完成事件，但不确定如何使用。请帮帮我。

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Web;
using System.Threading;
using System.Diagnostics;
using System.Windows.Forms;
using System.Drawing.Imaging;
namespace CC
{
    public partial class Form1 : Form
    {

        public Form1()
        {
            InitializeComponent();
        }
        private void Form1_Load(object sender, EventArgs e)
        {
            try
            {
                string url = "http://www.lll.com";
                webBrowser1.Navigate(new Uri(url));
                webBrowser1.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(webBrowser1_DocumentCompleted);
            }
            catch (Exception ex)
            {
            }
        }
        private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
        {
            string AbsoluteURL = e.Url.AbsolutePath.ToString();
            int count = 0;

            switch (AbsoluteURL)
            {
                case "Page1":
                    var loginControl = webBrowser1.Document.GetElementById("user");
                    var passwordControl = webBrowser1.Document.GetElementById("password");
                    var btn = webBrowser1.Document.GetElementById("Submit");
                    if (loginControl != null)
                        loginControl.SetAttribute("value", "XXX");
                    if (passwordControl != null)
                        passwordControl.SetAttribute("value", "YYY");
                    var elems = webBrowser1.Document.GetElementsByTagName("input");
                    foreach (HtmlElement elem in elems)
                    {
                        if (elem.GetAttribute("tabindex") == "3")
                        {
                            elem.InvokeMember("click");
                        }
                    }
                    break;

  case"Page2":  // THIS IS NOT WORKING. TAKING SCREEN SHOT BEFORE PAGE GETTING LOADED FULLY. NEED HELP HERE
                    using (Bitmap bitmap = new Bitmap(webBrowser1.Width, webBrowser1.Height, PixelFormat.Format24bppRgb))
        using (Graphics graphics = Graphics.FromImage(bitmap))
        {
            graphics.CopyFromScreen(
                PointToScreen(webBrowser1.Location),
                new Point(0, 0),
                webBrowser1.Size);
            bitmap.Save(@"C:123.bmp");
        }
                    break;
                default:
                    Console.WriteLine("Better try again");
                    break;

            }
        }

        }

    }
}

Answer 1

试试这个。

protected void Capture(object sender, EventArgs e)
{
    string url = "www.google.com";
    Thread thread = new Thread(delegate()
    {
        using (WebBrowser browser = new WebBrowser())
        {
            browser.ScrollBarsEnabled = false;
            browser.AllowNavigation = true;
            browser.Navigate(url);
            browser.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(DocumentCompleted);
            while (browser.ReadyState != WebBrowserReadyState.Complete)
            {
                System.Windows.Forms.Application.DoEvents();
            }
        }
    });
    thread.SetApartmentState(ApartmentState.STA);
    thread.Start();
    thread.Join();
}
 
private void DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
    WebBrowser browser = sender as WebBrowser;
       //do what do you want
}

Answer 2

根据我的经验，导航和文档加载与实际呈现文档不同。我会查看ReadyState https://msdn.microsoft.com/en-us/library/system.windows.forms.webbrowserreadystate%28v=vs.110%29.aspx 以确定文档是否实际呈现而不仅仅是加载。