tion SendMessage Lib "user32" _
Alias "SendMessageA" ( _
ByVal hwnd As Long, ByVal wMsg As Long, _
ByVal wParam As Long, lParam As Any) As Long
Public Const HTCAPTION = 2
Public Const WM_NCLBUTTONDOWN = &HA1
然后，在 Form_MouseDown 事件中：
Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
ReleaseCapture
SendMessage hwnd, WM_NCLBUTTONDOWN, HTCAPTION, 0&
End Sub
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快速选择全部项目
我们在使用 List 控件时，经常需要全部选择其中的项目，在项目较少时，我们可以逐项设置 Selected 来选择全部的项目，但当项目较多时，这样做就比较费时，其实，我们可以用 API 函数来简单实现此功能：
Dim nRet As Long
Dim bState as Boolean
bState=True
nRet = SendMessage(lstList.hWnd, LB_SETSEL, bState, -1)
函数声明：
Public Declare Function SendMessage Lib "User32" Alias "SendMessageA" ( ByVal hWnd As Long, ByVal wMsg As Integer, ByVal wParam As Long, ByVal lParam As Long) As Long
Public Const WM_USER = &H400
Public Const LB_SETSEL = (WM_USER + 6)
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真正删除数据库的记录
大家知道，缺省情况下，VB 删除记录只是把记录作上个删除标志而已，并没有真正删除。要真正删除记录，你可以使用 VB 提供的以下方法：BeginTrans、CommitTrans、RollBack。其中，BeginTrans 方法开始记录数据库的变动，CommitTrans 方法确认数据库的变动，而 RollBack 方法则可以恢复被删除或修改的记录。它们可以嵌套使用。因此，要恢复被删除的记录，应该在使用 BeginTrans 方法之后及使用 CommiTrans 方法之前使用 RollBack 方法。
[返回技巧索引]
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显示动画鼠标图标
Win95 的动画鼠标为应用程序增色不少，而 VB 则只提供一般的鼠标图标支持。要用 VB 显示动画鼠标形状，你可以使用以下方法：
函数声明：
Public Const GCL_HCURSOR = -12
Declare Function ClipCursor Lib "user32" (lpRect As Any) As Long
Declare Function DestroyCursor Lib "user32" (ByVal hCursor As Any) As Long
Declare Function LoadCursorFromFile Lib "user32" Alias "LoadCursorFromFileA" (ByVal lpFileName As String) As Long
Declare Function SetClassLong Lib "user32" Alias "SetClassLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Declare Function GetClassLong Lib "user32" Alias "GetClassLongA" (ByVal hwnd As Long, ByVal nIndex As Long) As Long
使用：
Dim mhBaseCursor As Long, mhAniCursor As Long
Dim lResult As Long
mhAniCursor = LoadCursorFromFile("c:\windows\cursors\appstart.ani")
lResult = SetClassLong((hwnd), GCL_HCURSOR, mhAniCursor)
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