请教一个画线的问题

[yoshubom]

例如我想画一条直线，鼠标第一次按下的时候确定起始点，然后这条线的另一端一直随着鼠标的移动而变化着，直到再次次按下左键的时候才真正使这条直线定型。如果按下右键则取消此次画线。请问用API可以实现吗？请高手讲讲方法，谢谢！

[303afei]

Movetoex
Lineto

[yoshubom]

我是说鼠标移动的过程中也出现直线，但是这条线是活动，直到再次按鼠标的时候才确定一条固定的直线。

[province_]

不需要API，只要VB的LINE控件就可以了。颜色随便定，画笔用XOR。其他的不说你也会了。

[province_]

Dim x1 As Long, y1 As Long

Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Button = 1 Then
x1 = X
y1 = Y
Line1.x1 = x1
Line1.y1 = y1
Line1.Visible = True
Else
Line1.Visible = False
End If
End Sub

Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Line1.Visible = True Then
Line1.X2 = X
Line1.Y2 = Y
End If
End Sub

[province_]

漏了一条
按下左键的时候判断LINE的可见性，若可见，则先使之隐藏，但其X1Y1、X2Y2用于真正画一条线。

[province_]

Dim x1 As Long, y1 As Long

Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Button = 1 Then

If Line1.Visible = False Then
x1 = X
y1 = Y
Line1.x1 = x1
Line1.y1 = y1
Line1.Visible = True
Else
Line1.Visible = False
DoEvents
Line (x1, y1)-(X, Y), vbBlack
End If

Else
Line1.Visible = False
End If
End Sub

Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Line1.Visible = True Then
Line1.X2 = X
Line1.Y2 = Y
End If
End Sub

[yoshubom]

多谢province_(雍昊)的热心回复，但是我的这个项目一定要用API，不然的话会被其他东西挡住的。