如何:使用线条、曲线和形状创建图形
更新:2007 年 11 月
若要创建图形,请构造 GraphicsPath,然后调用诸如 AddLine 和 AddCurve 的方法,向路径中添加基元。
示例
下面的代码示例创建具有图形的路径:
第一个示例创建具有单一图形的路径。该图形由一段弧组成。该弧的扫描角为 -180 度,此角度在默认的坐标系中是按逆时针方向旋转的。
第二个示例创建具有两个图形的路径。第一个图形是一段弧,后跟一条直线。第二个图形是一条直线,后跟一条曲线,再后面又是一条直线。第一个图形的左边是敞开的;第二个图形是闭合的。
Dim path As New GraphicsPath()
path.AddArc(175, 50, 50, 50, 0, -180)
e.Graphics.DrawPath(New Pen(Color.FromArgb(128, 255, 0, 0), 4), path)
GraphicsPath path = new GraphicsPath();
path.AddArc(175, 50, 50, 50, 0, -180);
e.Graphics.DrawPath(new Pen(Color.FromArgb(128, 255, 0, 0), 4), path);
' Create an array of points for the curve in the second figure.
Dim points As Point() = { _
New Point(40, 60), _
New Point(50, 70), _
New Point(30, 90)}
Dim path As New GraphicsPath()
path.StartFigure() ' Start the first figure.
path.AddArc(175, 50, 50, 50, 0, -180)
path.AddLine(100, 0, 250, 20)
' First figure is not closed.
path.StartFigure() ' Start the second figure.
path.AddLine(50, 20, 5, 90)
path.AddCurve(points, 3)
path.AddLine(50, 150, 150, 180)
path.CloseFigure() ' Second figure is closed.
e.Graphics.DrawPath(New Pen(Color.FromArgb(255, 255, 0, 0), 2), path)
// Create an array of points for the curve in the second figure.
Point[] points = {
new Point(40, 60),
new Point(50, 70),
new Point(30, 90)};
GraphicsPath path = new GraphicsPath();
path.StartFigure(); // Start the first figure.
path.AddArc(175, 50, 50, 50, 0, -180);
path.AddLine(100, 0, 250, 20);
// First figure is not closed.
path.StartFigure(); // Start the second figure.
path.AddLine(50, 20, 5, 90);
path.AddCurve(points, 3);
path.AddLine(50, 150, 150, 180);
path.CloseFigure(); // Second figure is closed.
e.Graphics.DrawPath(new Pen(Color.FromArgb(255, 255, 0, 0), 2), path);
编译代码
前面的示例是为使用 Windows 窗体而设计的,它们需要 Paint 事件处理程序的参数 PaintEventArgs e。