我想抓取网页。问题是，此网页具有只能单击的加密链接。使用webBrowser.Navigate无法正常工作。我设法模拟了一个点击动作，它打开了一个新窗口。现在，我要获取新窗口的网址。
private void Form1_Load(object sender, EventArgs e)
{
webBrowser1.Navigate(@"http://www.downarchive.ws/software/downloaders/795011-easy-mp3-downloader-4536.html");
}
private void webBrowser1_Navigated(object sender, WebBrowserNavigatedEventArgs e)
{
HtmlElementCollection links = webBrowser1.Document.GetElementsByTagName("a");
foreach (HtmlElement link in links)
{
if (link.GetAttribute("href").Contains(@"http://www.downarchive.ws/engine/go.php?url="))
{
link.InvokeMember("Click");
break;
}
}
}
private void webBrowser1_NewWindow(object sender, CancelEventArgs e)
{
var webBrowser = (WebBrowser)sender;
MessageBox.Show(webBrowser.Url.ToString());
}
1）您不需要调用click。最好使用导航方法。当您调用click时，链接可能会在新窗口中打开，可能会执行一些其他的javascript，等等。
2）如果您需要在所有重定向后获取url，则存在DocumentCompleted事件：
WebBrowserDocumentCompletedEventHandler onDocumentCompleted = (sender, e) => {
Uri theUlrThatYouNeed = e.Url;
webBrowser1.DocumentCompleted -= onDocumentCompleted;
};
webBrowser1.DocumentCompleted += onDocumentCompleted;
webBrowser1.Navigate("your encrypted url");
3）如果在外部IE窗口中打开了链接，则该链接已不存在-您无法控制外部浏览器并从中接收事件。有时，重定向可以打开新窗口。为防止这种情况，可以使用扩展的WebBrowser类：
namespace ExtendedWebBrowser {
[ComImport, TypeLibType(TypeLibTypeFlags.FHidden),
InterfaceType(ComInterfaceType.InterfaceIsIDispatch),
Guid("34A715A0-6587-11D0-924A-0020AFC7AC4D")]
public interface DWebBrowserEvents2 {
/// <summary>
///
/// </summary>
/// <param name="ppDisp">
/// An interface pointer that, optionally, receives the IDispatch interface
/// pointer of a new WebBrowser object or an InternetExplorer object.
/// </param>
/// <param name="Cancel">
/// value that determines whether the current navigation should be canceled
/// </param>
/// <param name="dwFlags">
/// The flags from the NWMF enumeration that pertain to the new window
/// See http://msdn.microsoft.com/en-us/library/bb762518(VS.85).aspx.
/// </param>
/// <param name="bstrUrlContext">
/// The URL of the page that is opening the new window.
/// </param>
/// <param name="bstrUrl">The URL that is opened in the new window.</param>
[DispId(0x111)]
void NewWindow3(
[In, Out, MarshalAs(UnmanagedType.IDispatch)] ref object ppDisp,
[In, Out] ref bool Cancel,
[In] uint dwFlags,
[In, MarshalAs(UnmanagedType.BStr)] string bstrUrlContext,
[In, MarshalAs(UnmanagedType.BStr)] string bstrUrl);
}
public partial class WebBrowserEx : WebBrowser {
AxHost.ConnectionPointCookie cookie;
DWebBrowserEvent2Helper helper;
[Browsable(true)]
public event EventHandler<WebBrowserNewWindowEventArgs> NewWindow3;
[PermissionSetAttribute(SecurityAction.LinkDemand, Name = "FullTrust")]
public WebBrowserEx() {
}
/// <summary>
/// Associates the underlying ActiveX control with a client that can
/// handle control events including NewWindow3 event.
/// </summary>
[PermissionSetAttribute(SecurityAction.LinkDemand, Name = "FullTrust")]
protected override void CreateSink() {
base.CreateSink();
helper = new DWebBrowserEvent2Helper(this);
cookie = new AxHost.ConnectionPointCookie(
this.ActiveXInstance, helper, typeof(DWebBrowserEvents2));
}
/// <summary>
/// Releases the event-handling client attached in the CreateSink method
/// from the underlying ActiveX control
/// </summary>
[PermissionSetAttribute(SecurityAction.LinkDemand, Name = "FullTrust")]
protected override void DetachSink() {
if (cookie != null) {
cookie.Disconnect();
cookie = null;
}
base.DetachSink();
}
/// <summary>
/// Raises the NewWindow3 event.
/// </summary>
protected virtual void OnNewWindow3(WebBrowserNewWindowEventArgs e) {
if (this.NewWindow3 != null) {
this.NewWindow3(this, e);
}
}
private class DWebBrowserEvent2Helper : StandardOleMarshalObject, DWebBrowserEvents2 {
private WebBrowserEx parent;
public DWebBrowserEvent2Helper(WebBrowserEx parent) {
this.parent = parent;
}
/// <summary>
/// Raise the NewWindow3 event.
/// If an instance of WebBrowser2EventHelper is associated with the underlying
/// ActiveX control, this method will be called When the NewWindow3 event was
/// fired in the ActiveX control.
/// </summary>
public void NewWindow3(ref object ppDisp, ref bool Cancel, uint dwFlags,
string bstrUrlContext, string bstrUrl) {
var e = new WebBrowserNewWindowEventArgs(bstrUrl, Cancel);
this.parent.OnNewWindow3(e);
Cancel = e.Cancel;
}
}
}
public class WebBrowserNewWindowEventArgs : EventArgs {
public String Url { get; set; }
public Boolean Cancel { get; set; }
public WebBrowserNewWindowEventArgs(String url, Boolean cancel) {
this.Url = url;
this.Cancel = cancel;
}
}
}
void WebBrowser_NewWindow(object sender, WebBrowserNewWindowEventArgs e) {
if (!string.IsNullOrEmpty(e.Url)) {
//Prevent new window
e.Cancel = true;
// Navigate to url from new window
Navigate(e.Url);
}
}
因此，如果您在WebBrowser控件的改进版本上进行替换，则可以防止出现新窗口。
您可以使用文档事件来检索单击的鼠标下的元素并将其存储为currentElement，然后在Web浏览器的NewWindow事件上，阅读href的currentElement并导航至该元素。
// after the document loaded
webBrowser1.Document.MouseMove += Document_MouseMove;
//On document mouse move, set the current Element
HtmlElement curElement;
void Document_MouseMove(object sender, HtmlElementEventArgs e)
{
curElement = webBrowser1.Document.GetElementFromPoint(e.ClientMousePosition);
}
// Now you have the clicked element
void webBrowser1_NewWindow(object sender, CancelEventArgs e)
{
e.Cancel = true;
if (curElement != null && curElement.TagName == "A")
{
string href = curElement.GetAttribute("href");
// do whatever
}
}
我知道这个问题已经很老了，但是我是这样解决的：添加新的引用，在COM中选择Microsoft Internet Controls，然后在代码中，在打开新窗口的单击之前添加以下内容：
SHDocVw.WebBrowser_V1 axBrowser = (SHDocVw.WebBrowser_V1)webBrowser1.ActiveXInstance;
axBrowser.NewWindow += axBrowser_NewWindow;
然后添加以下方法：
void axBrowser_NewWindow(string URL, int Flags, string TargetFrameName, ref object PostData, string Headers, ref bool Processed)
{
Processed = true;
webBrowser1.Navigate(URL);
}