删除图元操作是针对选择集中的图元的,它需要完成下面的操作:
·将选择集中的图元从图元集合类中删除;
·清空选择集;
·重画图元,将删除的图元从屏幕上删除。
code.vb.net
Private Sub mnuDelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuDelete.Click
Dim g As Graphics = Me.CreateGraphics
Dim i As Integer
For i = 0 To geSels.Count - 1
geSels(i).Draw(g, geDrawMode.Delete)
ges.Remove(geSels(i))
Next i
geSels.RemoveRange(0, geSels.Count)
End Sub
添加代码以后,运行程序,单击“选择”菜单中的“删除”菜单项,当前被选中的图形将从内存中和屏幕上被删除掉。