How to call the api clipcursor to fix mouse in the region?

[liangchu]

hi,I want to call the api function clipcursor to fix mouse in the region on a picturebox. But it has no effction. I don't know why it is.My code is following:
Private Type RECT
left As Long
top As Long
right As Long
bottom As Long
End Type

Private Declare Function ClipCursor Lib "user32" (lpRect As RECT) As Long
Dim D As RECT
Private Sub Form_Load()
Picture1.Scale (-10, 10)-(10, -10)
D.left = -8: D.top = 8: D.right = 8: D.bottom = -8
End Sub

Private Sub Picture1_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
dim t as long
t = ClipCursor(D)
End Sub

Please give me guide about it. Thanks a lot.