五、获得Ie窗口 mshtml.IHTMLDocument2
本小节是比较关键的一步，从Internet Explorer_Server获得IHTMLDocument2对象
使用到的api函数：
1、RegisterWindowMessage()函数定义一个新的窗口消息
Private Declare Function RegisterWindowMessage Lib "user32" Alias "RegisterWindowMessageA" (
ByVal lpString As String) As Integer2、SendMessageTimeout()函数将指定的消息发送到一个或多个窗口
Private Declare Function SendMessageTimeout Lib "user32" Alias "SendMessageTimeoutA" (
ByVal hWND As Integer,ByVal msg As Integer,ByVal wParam As Integer,ByRef lParam As Integer,ByVal fuFlags As Integer,ByVal uTimeout As Integer,ByRef lpdwResult As Integer) As Integer
Private Declare Function ObjectFromLresult Lib "oleacc" (
ByVal lResult As Integer,ByRef riid As Guid,ByRef ppvObject As mshtml.IHTMLDocument2) As Integer
4、用到的常量：
Private Const SMTO_ABORTIFHUNG = &H2
Private Const SMTO_NOTIMEOUTIFNOTHUNG = &H8
具体代码：
''' <summary>
''' 从Internet Explorer_Server获得IHTMLDocument2对象
''' </summary>
''' <param name="IEShwnd">Internet Explorer_Server 句柄</param>
''' <returns></returns>
''' <remarks></remarks>
'''
Public Function getDocumentfromIES(ByVal IEShwnd As Integer) As mshtml.IHTMLDocument2
Dim WM_Html_GETOBJECT As Integer
WM_Html_GETOBJECT = RegisterWindowMessage("WM_HTML_GETOBJECT")
Dim tempInt As Integer = 0
SendMessageTimeout(IEShwnd,WM_Html_GETOBJECT,SMTO_ABORTIFHUNG,1000,tempInt)
Dim GUID_IHTMLDocument As New Guid("{626FC520-A41E-11CF-A731-00A0C9082637}")
Dim I_IEdocument As mshtml.IHTMLDocument2
If ObjectFromLresult(tempInt,GUID_IHTMLDocument,I_IEdocument) = 0 Then
Return I_IEdocument
End If
Return Nothing
End Function
通过getDocumentfromIES()就可以获得某个Internet Explorer_Server关联的IHTMLDocument2
由于.net平台下C#和vb.NET很相似，本文也可以为C#爱好者提供参考。
学习更多vb.net知识，请参看vb.net 教程 目录