C#-将pictureBox中的坐标平移到中心\绘制坐标系\坐标轴

 在pictureBox中绘制图像，将坐标轴平移到中心（默认在pictureBox的左上角），并绘制坐标轴

--该段代码可以放在pictureBox的Paint事件里

Graphics myGraohics = e.Graphics;
//坐标系变换-先平移后缩放
myGraphics.TranslateTransform(pictureBox1.Width / 2, pictureBox1.Height / 2, MatrixOrder.Prepend);  //平移变换
myGraphics.ScaleTransform(1, -1, MatrixOrder.Prepend);  //继续进行缩放变换

//绘制平移、缩放后的坐标系，画笔采用蓝色-此时坐标原点已经到中心
Pen myPen = new Pen(Color.Black,3);

myPen.EndCap = LineCap.ArrowAnchor;  //设置线段终点的样式
myGraphics.DrawLine(myPen, -pictureBox1.Width / 2, 0, pictureBox1.Width / 2, 0); //绘制X轴
myGraphics.DrawLine(myPen, 0, -pictureBox1.Height / 2, 0, pictureBox1.Height / 2); //绘制Y轴

#region 绘刻度线
myPen.EndCap = LineCap.NoAnchor;
int k = pictureBox1.Width / 50;
for (int i = 0; i <= k; i++) //X轴刻度线
            {
                myGraphics.DrawLine(myPen, 50 * i, 0, 50 * i, 15);
                myGraphics.DrawLine(myPen, -50 * i, 0, -50 * i, 15);
            }
k = pictureBox1.Height / 100;
for (int i = 0; i <= k; i++) //Y轴刻度线
            {
                myGraphics.DrawLine(myPen, 0, 50 * i, 10, 50 * i);
                myGraphics.DrawLine(myPen, 0, -50 * i, 10, -50 * i);
            }
#endregion