有一个名称为Form1的窗体，上面没有控件，设有以下程序(其中方法Pset(X，Y)的功能是在坐标X、Y处画一个点)： Dim cmdMave AS Boolean Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single) cmdmave=True End Sub Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single) If cmdmave Then Form1.Pset(X,Y) End If End Sub Private Sub Form_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single) cmdmave=False End Sub 此程序的功能是