如何使用 GDI+ 绘制椭圆和圆。
要绘制椭圆,您需要指定外部矩形。 GDI+ 负责其余的工作。 DrawEllipse 绘制一个由一对坐标、一个高度和一个宽度指定的矩形定义的椭圆(高度和宽度相等的椭圆是一个圆)。
要绘制椭圆,应用程序创建一支笔和四个坐标(或者一个矩形),然后调用 DrawEllipse。
Private Sub Form1_Paint(ByVal sender As System.Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles MyBase.Paint ' Create Pens Dim redPen As New Pen(Color.Red, 6) Dim bluePen As New Pen(Color.Blue, 4) Dim greenPen As New Pen(Color.Green, 2) ' Create a rectangle Dim rect As New Rectangle(80, 80, 50, 50) ' Draw ellipses e.Graphics.DrawEllipse(greenPen, 100.0F, 100.0F, 10.0F, 10.0F) e.Graphics.DrawEllipse(redPen, rect) e.Graphics.DrawEllipse(bluePen, 60, 60, 90, 90) e.Graphics.DrawEllipse(greenPen, 40.0F, 40.0F, 130.0F, 130.0F) 'Dispose of objects redPen.Dispose() greenPen.Dispose() bluePen.Dispose() End Sub
日期:2020-06-02 22:16:03 来源:oir作者:oir