如何用PostMessage 后台发送鼠标点击 窗体任意设置的位置

看了这几年关于PostMessage 后台发送鼠标点击 窗体任意设置的位置，居然没有发现一个代码是可以实现的，郁闷啊，不知道这些代码错误在什么地方

VB code

Private Declare Function PostMessage Lib "user32.dll" Alias "PostMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Private Const WM_LBUTTONDOWN As Long = &H201
Private Const WM_LBUTTONUP As Long = &H202

Private Sub Command1_Click()
    SendClick Me.hwnd, 10, 10
End Sub

Private Sub Form_Click()
    MsgBox "dasd"
End Sub

Private Function SendClick(hwnd As Long, mX As Long, mY As Long)
    '发送点击消息
    Dim I As Long
    I = PostMessage(hwnd, WM_LBUTTONDOWN, 0, (mX And &HFFFF) + (mY And &HFFFF) * &H10000)
    I = PostMessage(hwnd, WM_LBUTTONUP, 0, (mX And &HFFFF) + (mY And &HFFFF) * &H10000)
End Function

你要是说 hwnd不对，所以没有发送到，好像又不是这么回事情，不知道为什么。现在难道高手都不在了吗？

PostMessage设置窗体位置？楼主为什么舍本求末？