Question

求用vb编一段简单的用鼠标拖动画直线的程序！

就是类似与vb中画直线的控件的那种画图程序，在点按下鼠标左键的同时开始画线，抬起鼠标左键的地方是终点，做一条线，线的颜色要可以自己调，不过在拖动鼠标时可以看到划线的过程以便调整，我自己编的时候，因为拖到哪里就会把线画到哪里，不能删掉原来的线，所以一拖动鼠标就会出现好多线，有人说要把先前拖出来的线和背景色异或一下之类的，我不知道该怎么做，谁能帮帮我！多谢！
回一楼沙发的那位，不好意思，因为还有其他的背景图，所以不能用Form1.Cls语句吧？

Answer 1

Dim xpos As Single, ypos As Single
Private Sub Form_Load()
Me.MousePointer = 2
End Sub
Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
'若要自己调颜色 工程-部件-microsoft common dialog control 6.0打钩-确定，添加一个commondialog控件并去掉下面两句的注释符
'If Button = 2 Then Me.CommonDialog1.ShowColor
'Me.ForeColor = Me.CommonDialog1.Color
Me.AutoRedraw = False
xpos = X: ypos = Y
End Sub
Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
Me.Refresh
If Button = 1 Then Line (xpos, ypos)-(X, Y)
End Sub
Private Sub Form_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
Me.AutoRedraw = True
Line (xpos, ypos)-(X, Y)
End Sub

Answer 2

Public WithEvents Liness As Line
Public Counts As Integer
Public isCan As Boolean
Private Sub Form_Load()
Counts = 0
isCan = False
End Sub

Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Button = 1 Then
Set Liness = Controls.Add("vb.line", "Liness" & Counts)
isCan = True
Counts = Count + 1
Liness.x1 = X
Liness.y1 = Y
End If
End Sub

Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Button = 1 And isCan = True Then
Liness.Visible = True

Liness.X2 = X
Liness.Y2 = Y

End If
End Sub

Private Sub Form_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
isCan = False
End Sub