我正在使用WinForms网页浏览器,我想在页面无效时显示自定义错误html,但我无法弄清楚如何做到这一点。我有这个小片段用于显示它:
if (wb_Main.Document != null)
{ wb_Main.Document.Write(string.Empty); }
wb_Main.DocumentText = html;
我在SO上发现了一些包含WebBrowser的代码,以便进入似乎工作正常的导航错误事件。但是每当我尝试在错误事件中设置html时,我都会遇到异常:
System.Runtime.InteropServices.COMException: The requested resource is in use. (Exception from HRESULT: 0x800700AA)
使用堆栈跟踪:
at System.Windows.Forms.UnsafeNativeMethods.IWebBrowser2.Navigate2(Object& URL, Object& flags, Object& targetFrameName, Object& postData, Object& headers)
at System.Windows.Forms.WebBrowser.PerformNavigate2(Object& URL, Object& flags, Object& targetFrameName, Object& postData, Object& headers)
at System.Windows.Forms.WebBrowser.set_Url(Uri value)
at System.Windows.Forms.WebBrowser.set_DocumentStream(Stream value)
at System.Windows.Forms.WebBrowser.set_DocumentText(String value)
at RDES.CMI.Revit.CADDBrowser.UC_Browser.wb_Main_NavigateError(Object sender, WebBrowserNavigateErrorEventArgs e) in c:\RD\Projects\16-003 CADD Browser\Code\CADDBrowser\UC_Browser.xaml.cs:line 84
at RDES.CMI.Revit.CADDBrowser.WebBrowser2.OnNavigateError(WebBrowserNavigateErrorEventArgs e) in c:\RD\Projects\16-003 CADD Browser\Code\CADDBrowser\WebBrowser2.cs:line 49
at RDES.CMI.Revit.CADDBrowser.WebBrowser2.WebBrowser2EventHelper.NavigateError(Object pDisp, Object& url, Object& frame, Object& statusCode, Boolean& cancel) in c:\RD\Projects\16-003 CADD Browser\Code\CADDBrowser\WebBrowser2.cs:line 69
我甚至尝试在导航错误处理程序中设置错误文本变量,然后等待文档已完成事件重新导航到错误文本,但文档已完成从不触发。导航错误后我触发的唯一事件是'status text changed'事件,当我尝试显示错误时会抛出相同的错误。
我最初使用的WPF浏览器控件做得非常好,但不幸的是我插入的程序似乎在WPF浏览器中存在一个主要问题(它在某些相对常见的情况下崩溃了程序)。
有办法做到这一点吗?我感觉有点卡住......
以下是我在此处找到的包装类的代码,以防需要:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Permissions;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace RDES.CMI.Revit.CADDBrowser
{
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);
}
}