大家都知道，vb.net封装了GDI，但是你死活找不到像vb6一样简单的代码

 

vb6是这样的：

 

Dim x1 As Integer

Dim x2 As Integer

Dim y1 As Integer

Dim y2 As Integer

Dim flag As Boolean

 

Private Sub Picture1_MouseDown(button As Integer, shift As Integer, x As Single, y As Single)

    flag = True

    x1 = x

    y1 = y

    Picture1.Line (x1, y1)-(x1 + 1, y1 + 1)

End Sub

 

Private Sub Picture1_MouseMove(button As Integer, shift As Integer, x As Single, y As Single)

 

    If flag = False Then

        Exit Sub

    End If

    

    If flag = True Then

        x2 = x

        y2 = y

        Picture1.Line (x1, y1)-(x2, y2)

        x1 = x2

        y1 = y2

    End If

    

End Sub

Private Sub Picture1_MouseUp(button As Integer, shift As Integer, x As Single, y As Single)

    flag = False

End Sub

而vb.net是这样的

 

Dim x1 As Integer

    Dim x2 As Integer

    Dim y1 As Integer

    Dim y2 As Integer

    Dim flag As Boolean = False

Private Sub PictureBox1_MouseDown(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseDown

        flag = True

        x1 = e.X

        y1 = e.Y

        x2 = e.X

        y2 = e.Y

    End Sub

 

    Private Sub PictureBox1_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseMove

        If flag = True Then

            x1 = e.X

            y1 = e.Y

            Dim Graph As Graphics

            Graph = Graphics.FromImage(PictureBox1.Image)

            PictureBox1.CreateGraphics.DrawLine(p, New Point(x1, y1), New Point(x2, y2))

            x2 = e.X

            y2 = e.Y

        End If

    End Sub

 

    Private Sub PictureBox1_MouseUp(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseUp

        flag = False

    End Sub

 现在终于明白了吧

 

那么如何清除呢？

 

vb6

 

Picture1.Cls

vb.net

 

PictureBox1.CreateGraphics.Clear(BackColor)

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版权声明：本文为CSDN博主「小虞163」的原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接及本声明。

原文链接：https://blog.csdn.net/weixin_56050945/article/details/122599106