怎么用VB判断屏幕上某点颜色是否与设定的颜色相同

Private Declare Function GetDC Lib "user32" (ByVal hwnd As Long) As Long
Private Declare Function ReleaseDC Lib "user32" (ByVal hwnd As Long, ByVal hdc As Long) As Long
Private Declare Function GetPixel Lib "gdi32" (ByVal hdc As Long, ByVal x As Long, ByVal y As Long) As Long

Private Sub Command1_Click()
h = GetDC(0) '取得整个屏幕的DC
Colr = GetPixel(h, 281, 190) '取颜色
ReleaseDC 0, hdc '释放hDC
If Colr = &H36a7d9 Then
MsgBox "相同"
Else
MsgBox "不同"
End If
End Sub