FindWindowEx
函数功能：该函数获得一个窗口的句柄，该窗口的类名和窗口名与给定的字符串相匹配。这个函数查找子窗口，从排在给定的子窗口后面的下一个子窗口开始。在查找时不区分大小写。
函数原型：HWND FindWindowEx（HWND hwndParent，HWND hwndChildAfter，LPCTSTR lpszClass，LPCTSTR lpszWindow）；
参数；
hwndParent：要查找子窗口的父窗口句柄。
如果hwndParent为NULL，则函数以桌面窗口为父窗口，查找桌面窗口的所有子窗口。
Windows NT5.0 and later：如果hwndParent是HWND_MESSAGE，函数仅查找所有消息窗口。
hwndChildAfter ：子窗口句柄。查找从在Z序中的下一个子窗口开始。子窗口必须为hwndPareRt窗口的直接子窗口而非后代窗口。如果HwndChildAfter为NULL，查找从hwndParent的第一个子窗口开始。如果hwndParent 和 hwndChildAfter同时为NULL，则函数查找所有的顶层窗口及消息窗口。
lpszClass：指向一个指定了类名的空结束字符串，或一个标识类名字符串的成员的指针。如果该参数为一个成员，则它必须为前次调用theGlobaIAddAtom函数产生的全局成员。该成员为16位，必须位于lpClassName的低16位，高位必须为0。
lpszWindow：指向一个指定了窗口名（窗口标题）的空结束字符串。如果该参数为 NULL，则为所有窗口全匹配。返回值：如果函数成功，返回值为具有指定类名和窗口名的窗口句柄。如果函数失败，返回值为NULL。
若想获得更多错误信息，请调用GetLastError函数。
速查 NT：4.0对以上版本；Windows：95以上版本；Windows CE：不支持；头文件：winuser.h；库文件：user32．lib；Unicode：在Windows NT上实现为Unicode和ANSI两种版本。
在窗口列表中寻找与指定条件相符的第一个子窗口
返回值
Long，找到的窗口的句柄。如未找到相符窗口，则返回零。会设置GetLastError
参数表
参数 类型及说明
hWnd1 Long，在其中查找子的父窗口。如设为零，表示使用桌面窗口（通常说的顶级窗口都被认为是桌面的子窗口，所以也会对它们进行查找）
hWnd2 Long，从这个窗口后开始查找。这样便可利用对FindWindowEx的多次调用找到符合条件的所有子窗口。如设为零，表示从第一个子窗口开始搜索
lpsz1 String，欲搜索的类名。零表示忽略
lpsz2 String，欲搜索的类名。零表示忽略
相关例子：
'Example Name: Changing a VB Toolbar to a Rebar-Style Toolbar
'------------------------------------------------------------------------------
'
' BAS Moduel Code
'
'------------------------------------------------------------------------------
Option Explicit
Public Const WM_USER = &H400
Public Const TB_SETSTYLE = WM_USER + 56
Public Const TB_GETSTYLE = WM_USER + 57
Public Const TBSTYLE_FLAT = &H800
Public Declare Function SendMessage Lib "user32" _
Alias "SendMessageA" _
(ByVal hwnd As Long, _
ByVal wMsg As Long, _
ByVal wParam As Long, _
lParam As Any) As Long
Public Declare Function FindWindowEx Lib "user32" _
Alias "FindWindowExA" _
(ByVal hWnd1 As Long, _
ByVal hWnd2 As Long, _
ByVal lpsz1 As String, _
ByVal lpsz2 As String) As Long
'--end block--'
'------------------------------------------------------------------------------
'
' Form Code
'
'------------------------------------------------------------------------------
Option Explicit
Private Sub Form_Load()
With Combo1
.Width = Toolbar1.Buttons("combo1").Width
.Top = (Toolbar1.Height - Combo1.Height) 2
.Left = Toolbar1.Buttons("combo1").Left
.AddItem "Black" ' Add colours for text.
.AddItem "Blue"
.AddItem "Red"
.ListIndex = 0
End With
End Sub
Private Sub Command1_Click()
Dim style As Long
Dim hToolbar As Long
'get the handle of the toolbar
hToolbar = FindWindowEx(Toolbar1.hwnd, 0&, "ToolbarWindow32", vbNullString)
'retrieve the toolbar styles
style = SendMessage(hToolbar, TB_GETSTYLE, 0&, ByVal 0&)
'Set the new style flag
If style And TBSTYLE_FLAT Then
style = style Xor TBSTYLE_FLAT
Else: style = style Or TBSTYLE_FLAT
End If
'apply the new style to the toolbar
Call SendMessage(hToolbar, TB_SETSTYLE, 0, ByVal style)
Toolbar1.Refresh
End Sub
'Example Name:Disabling the Combo Edit Box
'------------------------------------------------------------------------------
'
' BAS Moduel Code
'
'------------------------------------------------------------------------------
Option Explicit
Public Const EM_SETREADONLY = &HCF
Public Declare Function SendMessage Lib "user32" _
Alias "SendMessageA" _
(ByVal hwnd As Long, _
ByVal wMsg As Long, _
ByVal wParam As Long, _
lParam As Any) As Long
Public Declare Function SetWindowText Lib "user32" _
Alias "SetWindowTextA" _
(ByVal hwnd As Long, _
ByVal lpString As String) As Long
Public Declare Function FindWindowEx Lib "user32" _
Alias "FindWindowExA" _
(ByVal hWnd1 As Long, _
ByVal hWnd2 As Long, _
ByVal lpsz1 As String, _
ByVal lpsz2 As String) As Long
'--end block--'
'------------------------------------------------------------------------------
'
' Form Code
'
'------------------------------------------------------------------------------
Option Explicit
Sub Form_Load()
'fill a combo with 10 of the
'system's screen fonts.
Dim i As Integer
For i = 1 To 10
Combo1.AddItem Screen.Fonts(i)
Next
End Sub
Private Sub Command1_Click()
Dim hwndEdit As Long
'get the handle to the edit portion
'of the combo control
hwndEdit = FindWindowEx(Combo1.hwnd, 0&, vbNullString, vbNullString)
If hwndEdit <> 0 Then
'prove you got it by changing its text (style 0 only)
Call SetWindowText(hwndEdit, "You can copy, but not change me :-)")
'and disable the edit control's editing ability
Call SendMessage(hwndEdit, EM_SETREADONLY, 1&, ByVal 0&)
End If
End Sub
'Example Name:Fixing the IE5/MsComCtrl 5 Toolbar Problem
'------------------------------------------------------------------------------
'
' BAS Moduel Code
'
'------------------------------------------------------------------------------
Option Explicit
Public Const WM_USER As Long = &H400
Public Const TB_SETSTYLE As Long = WM_USER + 56
Public Const TB_GETSTYLE As Long = WM_USER + 57
Public Const TBSTYLE_WRAPABLE As Long = &H200 'buttons to wrap when form resized
Public Const TBSTYLE_FLAT As Long = &H800 'flat IE3+ style toolbar
Public Const TBSTYLE_LIST As Long = &H1000 'places captions beside buttons
Public Declare Function SendMessage Lib "user32" _
Alias "SendMessageA" _
(ByVal hwnd As Long, _
ByVal wMsg As Long, _
ByVal wParam As Long, _
lParam As Any) As Long
Public Declare Function FindWindowEx Lib "user32" _
Alias "FindWindowExA" _
(ByVal hWnd1 As Long, _
ByVal hWnd2 As Long, _
ByVal lpsz1 As String, _
ByVal lpsz2 As String) As Long
'--end block--'
'------------------------------------------------------------------------------
'
' Form Code
'
'------------------------------------------------------------------------------
Option Explicit
Private Sub Form_Load()
'centre form
Me.Move (Screen.Width - Me.Width) 2, (Screen.Height - Me.Height) 2
Me.Show
'for the demo, make toolbars 1 and 3 flat
'args: ctrl horiz wrapable
CreateFlatToolbar Toolbar1, False, False
CreateFlatToolbar Toolbar3, True, False
'set toolbar 4 to horizontal. Since
'toolbar 2 retains the default
'appearance, no styles are specified.
'args: ctrl horiz wrapable
CreateHorizontalToolbar Toolbar4, True, False
End Sub
Private Sub Command1_Click()
' ctrl, ndx, caption
SetToolbarCaption Toolbar1, 1, "Go Backwards"
SetToolbarCaption Toolbar2, 1, "Go Backwards"
SetToolbarCaption Toolbar3, 1, "Go Backwards"
SetToolbarCaption Toolbar4, 1, "Go Backwards"
'this is the code to produce the illustration 2 results
'Toolbar1.Buttons(1).Caption = "Go Backwards"
'Toolbar2.Buttons(1).Caption = "Go Backwards"
'Toolbar3.Buttons(1).Caption = "Go Backwards"
'Toolbar4.Buttons(1).Caption = "Go Backwards"
End Sub
Private Sub CreateFlatToolbar(TBar As Toolbar, _
fHorizontal As Boolean, _
fWrapable As Boolean)
Dim hTBar As Long
Dim style As Long
'to assure that the toolbar has correctly calculated
'the button widths based on the assigned captions,
'force a refresh
TBar.Refresh
'get the handle of the toolbar
hTBar = FindWindowEx(TBar.hwnd, 0&, "ToolbarWindow32", vbNullString)
'retrieve the current toolbar style
style = SendMessage(hTBar, TB_GETSTYLE, 0&, ByVal 0&)
style = style Or TBSTYLE_FLAT Or TBSTYLE_WRAPABLE
'if a horizontal layout was specified, add that style
If fHorizontal Then style = style Or TBSTYLE_LIST
'apply the new style to the toolbar and refresh
Call SendMessage(hTBar, TB_SETSTYLE, 0&, ByVal style)
TBar.Refresh
'now that the toolbar is flat, if the wrapable
'style is not desired, it can be removed.
'A refresh is not required.
If fWrapable = False Then
style = style Xor TBSTYLE_WRAPABLE
Call SendMessage(hTBar, TB_SETSTYLE, 0&, ByVal style)
End If
End Sub
Private Sub CreateHorizontalToolbar(TBar As Toolbar, _
fHorizontal As Boolean, _
fWrapable As Boolean)
Dim hTBar As Long
Dim style As Long
'get the handle of the toolbar
hTBar = FindWindowEx(TBar.hwnd, 0&, "ToolbarWindow32", vbNullString)
'retrieve the current toolbar style
style = SendMessage(hTBar, TB_GETSTYLE, 0&, ByVal 0&)
'Set the new style flags
If fHorizontal Then
style = style Or TBSTYLE_LIST
End If
If fWrapable Then
style = style Or TBSTYLE_WRAPABLE
End If
'apply the new style to the toolbar and refresh
Call SendMessage(hTBar, TB_SETSTYLE, 0&, ByVal style)
TBar.Refresh
End Sub
Private Sub SetToolbarCaption(TBar As Toolbar, _
TBIndex As Integer, _
newCaption As String)
Dim hTBar As Long
Dim inStyle As Long
Dim tempStyle As Long
'get the handle to the toolbar and its current style
hTBar = FindWindowEx(TBar.hwnd, 0&, "ToolbarWindow32", vbNullString)
inStyle = SendMessage(hTBar, TB_GETSTYLE, 0&, ByVal 0&)
'if the toolbar has had the flat style applied
If inStyle And TBSTYLE_FLAT Then
tempStyle = inStyle Xor TBSTYLE_FLAT
Call SendMessage(hTBar, TB_SETSTYLE, 0&, ByVal tempStyle)
TBar.Buttons(TBIndex).Caption = newCaption
TBar.Refresh
'restore the previous style, and refresh once more
Call SendMessage(hTBar, TB_SETSTYLE, 0&, ByVal inStyle)
TBar.Refresh
Else
'its not flat, so just change the text
TBar.Buttons(TBIndex).Caption = newCaption
End If
End Sub
'Example Name: Obtaining the Combo Box Edit Window Handle
'------------------------------------------------------------------------------
'
' BAS Moduel Code
'
'------------------------------------------------------------------------------
Option Explicit
Public Const CB_ADDSTRING = &H143
Public Const CB_SETITEMDATA = &H151
Public Declare Function FindWindowEx Lib "user32" _
Alias "FindWindowExA" _
(ByVal hWnd1 As Long, _
ByVal hWnd2 As Long, _
ByVal lpsz1 As String, _
ByVal lpsz2 As String) As Long
Public Declare Function SendMessage Lib "user32" _
Alias "SendMessageA" _
(ByVal hwnd As Long, _
ByVal wMsg As Long, _
ByVal wParam As Long, _
lParam As Any) As Long
Public Declare Function SetWindowText Lib "user32" _
Alias "SetWindowTextA" _
(ByVal hwnd As Long, _
ByVal lpString As String) As Long
'--end block--'
'------------------------------------------------------------------------------
'
' Form Code
'
'------------------------------------------------------------------------------
Option Explicit
Private Sub Command1_Click()
Dim hwndEdit As Long
'get the handle to the edit portion
'of the combo control
hwndEdit = FindWindowEx(Combo1.hwnd, 0&, vbNullString, vbNullString)
'prove you got it by changing its text (style 0 only)
Call SetWindowText(hwndEdit, "FindWindowEx found it!")
'add it to the list...
Call SendMessage(Combo1.hwnd, CB_ADDSTRING, _
0&, ByVal "FindWindowEx: Edit handle is " & CStr(hwndEdit))
End Sub