不用cls方法
Dim startx, starty As Single
Dim drawing As Boolean

Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
    If Button = 1 Then
    Form1.AutoRedraw = False
    startx = X
    starty = Y
    drawing = True
    End If
End Sub

Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
    If drawing Then
    Form1.Line (startx, starty)-(X, Y)
    Form1.MousePointer = 2
    End If
End Sub

还有个问题，当新线移动时会擦除以前的线，怎么办？

这样又不能像橡皮筋那样拉伸了，怎么改成我原来那种不用一直按着鼠标的画法？

谢谢了