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我在我的winform上有WebBrowser控件。當我嘗試瀏覽到一些網址我得到標準的IE錯誤頁面,如:WebBrowser控件頁面加載錯誤
- 「導航到網頁已取消」
- 「地址是無效」
- 「頁面無法裝」
- 等
我需要處理這些錯誤,並返回自定義錯誤消息給用戶。有什麼辦法可以解決這個問題嗎?
我在我的winform上有WebBrowser控件。當我嘗試瀏覽到一些網址我得到標準的IE錯誤頁面,如:WebBrowser控件頁面加載錯誤
我需要處理這些錯誤,並返回自定義錯誤消息給用戶。有什麼辦法可以解決這個問題嗎?
你要處理的NavigateError事件如圖here
編輯:包括鏈接示例代碼:
using System;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Security.Permissions;
namespace WebBrowserExtensibility
{
[PermissionSetAttribute(SecurityAction.Demand, Name="FullTrust")]
public class Form1 : Form
{
[STAThread]
public static void Main()
{
Application.Run(new Form1());
}
private WebBrowser2 wb = new WebBrowser2();
public Form1()
{
wb.Dock = DockStyle.Fill;
wb.NavigateError += new
WebBrowserNavigateErrorEventHandler(wb_NavigateError);
Controls.Add(wb);
// Attempt to navigate to an invalid address.
wb.Navigate("www.widgets.microsoft.com");
}
private void wb_NavigateError(
object sender, WebBrowserNavigateErrorEventArgs e)
{
// Display an error message to the user.
MessageBox.Show("Cannot navigate to " + e.Url);
}
}
public class WebBrowser2 : WebBrowser
{
AxHost.ConnectionPointCookie cookie;
WebBrowser2EventHelper helper;
[PermissionSetAttribute(SecurityAction.LinkDemand, Name="FullTrust")]
protected override void CreateSink()
{
base.CreateSink();
// Create an instance of the client that will handle the event
// and associate it with the underlying ActiveX control.
helper = new WebBrowser2EventHelper(this);
cookie = new AxHost.ConnectionPointCookie(
this.ActiveXInstance, helper, typeof(DWebBrowserEvents2));
}
[PermissionSetAttribute(SecurityAction.LinkDemand, Name="FullTrust")]
protected override void DetachSink()
{
// Disconnect the client that handles the event
// from the underlying ActiveX control.
if (cookie != null)
{
cookie.Disconnect();
cookie = null;
}
base.DetachSink();
}
public event WebBrowserNavigateErrorEventHandler NavigateError;
// Raises the NavigateError event.
protected virtual void OnNavigateError(
WebBrowserNavigateErrorEventArgs e)
{
if (this.NavigateError != null)
{
this.NavigateError(this, e);
}
}
// Handles the NavigateError event from the underlying ActiveX
// control by raising the NavigateError event defined in this class.
private class WebBrowser2EventHelper :
StandardOleMarshalObject, DWebBrowserEvents2
{
private WebBrowser2 parent;
public WebBrowser2EventHelper(WebBrowser2 parent)
{
this.parent = parent;
}
public void NavigateError(object pDisp, ref object url,
ref object frame, ref object statusCode, ref bool cancel)
{
// Raise the NavigateError event.
this.parent.OnNavigateError(
new WebBrowserNavigateErrorEventArgs(
(String)url, (String)frame, (Int32)statusCode, cancel));
}
}
}
// Represents the method that will handle the WebBrowser2.NavigateError event.
public delegate void WebBrowserNavigateErrorEventHandler(object sender,
WebBrowserNavigateErrorEventArgs e);
// Provides data for the WebBrowser2.NavigateError event.
public class WebBrowserNavigateErrorEventArgs : EventArgs
{
private String urlValue;
private String frameValue;
private Int32 statusCodeValue;
private Boolean cancelValue;
public WebBrowserNavigateErrorEventArgs(
String url, String frame, Int32 statusCode, Boolean cancel)
{
urlValue = url;
frameValue = frame;
statusCodeValue = statusCode;
cancelValue = cancel;
}
public String Url
{
get { return urlValue; }
set { urlValue = value; }
}
public String Frame
{
get { return frameValue; }
set { frameValue = value; }
}
public Int32 StatusCode
{
get { return statusCodeValue; }
set { statusCodeValue = value; }
}
public Boolean Cancel
{
get { return cancelValue; }
set { cancelValue = value; }
}
}
// Imports the NavigateError method from the OLE DWebBrowserEvents2
// interface.
[ComImport, Guid("34A715A0-6587-11D0-924A-0020AFC7AC4D"),
InterfaceType(ComInterfaceType.InterfaceIsIDispatch),
TypeLibType(TypeLibTypeFlags.FHidden)]
public interface DWebBrowserEvents2
{
[DispId(271)]
void NavigateError(
[In, MarshalAs(UnmanagedType.IDispatch)] object pDisp,
[In] ref object URL, [In] ref object frame,
[In] ref object statusCode, [In, Out] ref bool cancel);
}
}
我會閱讀例子並使用它。謝謝。還有另一個問題。當用戶嘗試導航到文件鏈接時(當用戶嘗試下載文件時),我需要處理這種情況 - 我應該拒絕這樣的請求。這種情況是否也可以解決? – 2010-11-19 14:22:55
如果您還處理Navigate事件,則可以檢查URL(將成爲文件名),並將WebBrowserNavigatingEventArgs的Cancel屬性設置爲true(如果它是文件而不是頁面)。儘管如此,這還是取決於能否區分文件下載與常規導航。 – stuartd 2010-11-19 14:32:49
那麼,我可以檢查我的代碼中的大部分文件擴展名(如果uri包含文件名)。但是有很多例子,當服務器可以響應某些流,這可以通過瀏覽器像二進制數據一樣檢測到,打開/保存/取消messagebox會顯示。我可以在將它展示給用戶之前捕獲這個消息框嗎? – 2010-11-19 14:44:34