在TextBox中如何得知Caret所在位置

　　 
　　在TextBox中如何得知Caret所在位置

作者: cww　

注释：在form中放一个textBox两个label
Const EM_GETSEL = &HB0
Const EM_LINEFROMCHAR = &HC9
Const EM_LINEINDEX = &HBB

Private 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 Sub GetCaretPos(ByVal hwnd5 As Long, LineNo As Long, ColNo As Long)
Dim i As Long, j As Long
Dim lParam As Long, wParam As Long
Dim k As Long
i = SendMessage(hwnd5, EM_GETSEL, wParam, lParam)
j = i / 2 ^ 16  注释：取得目前Caret所在前面有多少个byte
LineNo = SendMessage(hwnd5, EM_LINEFROMCHAR, j, 0) 注释：取得前面有多少行
LineNo = LineNo + 1
k = SendMessage(hwnd5, EM_LINEINDEX, -1, 0)
注释：取得目前caret所在行前面有多少个byte
ColNo = j - k + 1
End Sub

Private Sub Form_Load()
Dim LineNo As Long, ColNo As Long

Call GetCaretPos(Text1.hwnd, LineNo, ColNo)
Label1.Caption = LineNo
Label2.Caption = ColNo

End Sub

Private Sub Text1_KeyUp(KeyCode As Integer, Shift As Integer)
Dim LineNo As Long, ColNo As Long

Call GetCaretPos(Text1.hwnd, LineNo, ColNo)
Label1.Caption = LineNo
Label2.Caption = ColNo

End Sub

Private Sub Text1_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
Dim LineNo As Long, ColNo As Long

Call GetCaretPos(Text1.hwnd, LineNo, ColNo)
Label1.Caption = LineNo
Label2.Caption = ColNo

End Sub

原文转自：http://www.ltesting.net