C#窗体程序画倾斜一定角度的椭圆
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Drawing.Drawing2D; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; namespace Ellipse { public partial class Form1 : Form { PointF xyPoint = new PointF(); //左上角的X，Y坐标 PointF centerPoint = new PointF();//椭圆的中心点 PointF movePoint = new PointF(); PointF xiePointF=new PointF(); PointF xiedPointF = new PointF();//倾斜一定角度后的点 private double perAngle = 0; private double nowAngle; PointF[] pointFs=new PointF[201]; PointF[] pointFs1=new PointF[201];//与pointFs对称的点数组，椭圆是对称的 PointF[] xiePointFs=new PointF[201];//倾斜的椭圆上半部分 PointF[] xiePointFs1 = new PointF[201];//倾斜的椭圆下半部分，对称的部分 private float a =200; private float b =100; private float stepLength = 2;//通过X坐标逐次加2计算出Y坐标，将所有坐标存在数组中，用DrawCurve连接 private float xLength = 0;//点到坐标Y轴的线段距离 private float yLength = 0;//颠倒坐标X轴的线段距离 private float dbYlength = 0; private float xiedLength = 0;//点到椭圆中心点的线段长度 private int angle = 0;//倾斜的角度 public Form1() { InitializeComponent(); } private void panel1_Paint(object sender， PaintEventArgs e) { } private void panel1_MouseClick(object sender， MouseEventArgs e)////画布鼠标键点击事件，重画图形 { if (e.Button != MouseButtons.Left) { return; } if (this.textBox1.Text == "") { this.errorProvider1.SetError(this.textBox1， "请输入倾斜的角度"); return; } else { this.errorProvider1.SetError(this.textBox1， ""); } xyPoint.X = this.panel1.Width/2-200; xyPoint.Y = this.panel1.Height/2-100; centerPoint.X = xyPoint.X + a; centerPoint.Y = xyPoint.Y + b; Graphics graphics = this.panel1.CreateGraphics(); graphics.SmoothingMode = SmoothingMode.HighQuality; graphics.Clear(this.panel1.BackColor); Pen pen = new Pen(Color.Red); for (int index = 0; index < pointFs.Length; index++) { movePoint.X = index * stepLength + xyPoint.X; xLength = centerPoint.X - movePoint.X; yLength = (float)(Math.Sqrt((1 - (xLength * xLength) / 40000) * 10000)); movePoint.Y = b - yLength + xyPoint.Y; pointFs[index] = movePoint; } graphics.DrawCurve(pen， pointFs， 1.5f); for (int index = 0; index < pointFs1.Length; index++) { dbYlength = centerPoint.Y - pointFs[index].Y; pointFs1[index].Y = centerPoint.Y + dbYlength; pointFs1[index].X = pointFs[index].X; } graphics.DrawCurve(pen， pointFs1， 1.5f); for (int index = 0; index < pointFs.Length; index++) { xiePointF = pointFs[index]; double startAngle = Math.Atan2(xiePointF.Y - centerPoint.Y， xiePointF.X - centerPoint.X); string jiaodu = this.textBox1.Text; perAngle = int.Parse(jiaodu) * Math.PI / 180; nowAngle = startAngle + perAngle; xiedLength = (float)Math.Sqrt(Math.Pow(xiePointF.X - centerPoint.X， 2) + Math.Pow(xiePointF.Y - centerPoint.Y， 2)); xiedPointF.X = centerPoint.X - (float)(xiedLength * Math.Cos(nowAngle)); xiedPointF.Y = centerPoint.Y + (float)(xiedLength * Math.Sin(nowAngle)); xiePointFs[index] = xiedPointF; } graphics.DrawCurve(pen， xiePointFs， 1.5f); for (int index = 0; index < pointFs1.Length; index++) { xiePointF = pointFs1[index]; double startAngle = Math.Atan2(xiePointF.Y - centerPoint.Y， xiePointF.X - centerPoint.X); string jiaodu = this.textBox1.Text; perAngle = int.Parse(jiaodu) * Math.PI / 180; nowAngle = startAngle + perAngle; xiedLength = (float)Math.Sqrt(Math.Pow(xiePointF.X - centerPoint.X， 2) + Math.Pow(xiePointF.Y - centerPoint.Y， 2)); xiedPointF.X = centerPoint.X - (float)(xiedLength * Math.Cos(nowAngle)); xiedPointF.Y = centerPoint.Y + (float)(xiedLength * Math.Sin(nowAngle)); xiePointFs1[index] = xiedPointF; } graphics.DrawCurve(pen， xiePointFs1， 1.5f); } private void button1_Click(object sender， EventArgs e)//倾斜角度，每次递增10度 { angle += 10; this.textBox1.Text = angle.ToString(); if (this.textBox1.Text == "") { this.errorProvider1.SetError(this.textBox1， "请输入倾斜的角度"); return; } else { this.errorProvider1.SetError(this.textBox1， ""); } xyPoint.X = this.panel1.Width / 2-200; xyPoint.Y = this.panel1.Height / 2-100; centerPoint.X = xyPoint.X + a; centerPoint.Y = xyPoint.Y + b; Graphics graphics = this.panel1.CreateGraphics(); graphics.SmoothingMode = SmoothingMode.HighQuality; graphics.Clear(this.panel1.BackColor); Pen pen = new Pen(Color.Red); for (int index = 0; index < pointFs.Length; index++) { movePoint.X = index * stepLength + xyPoint.X; xLength = centerPoint.X - movePoint.X; yLength = (float)(Math.Sqrt((1 - (xLength * xLength) / 40000) * 10000)); movePoint.Y = b - yLength + xyPoint.Y; pointFs[index] = movePoint; } graphics.DrawCurve(pen， pointFs， 1.5f); for (int index = 0; index < pointFs1.Length; index++) { dbYlength = centerPoint.Y - pointFs[index].Y; pointFs1[index].Y = centerPoint.Y + dbYlength; pointFs1[index].X = pointFs[index].X; } graphics.DrawCurve(pen， pointFs1， 1.5f); for (int index = 0; index < pointFs.Length; index++) { xiePointF = pointFs[index]; double startAngle = Math.Atan2(xiePointF.Y - centerPoint.Y， xiePointF.X - centerPoint.X); string jiaodu = this.textBox1.Text; perAngle = int.Parse(jiaodu) * Math.PI / 180; nowAngle = startAngle + perAngle; xiedLength = (float)Math.Sqrt(Math.Pow(xiePointF.X - centerPoint.X， 2) + Math.Pow(xiePointF.Y - centerPoint.Y， 2)); xiedPointF.X = centerPoint.X - (float)(xiedLength * Math.Cos(nowAngle)); xiedPointF.Y = centerPoint.Y + (float)(xiedLength * Math.Sin(nowAngle)); xiePointFs[index] = xiedPointF; } graphics.DrawCurve(pen， xiePointFs， 1.5f); for (int index = 0; index < pointFs1.Length; index++) { xiePointF = pointFs1[index]; double startAngle = Math.Atan2(xiePointF.Y - centerPoint.Y， xiePointF.X - centerPoint.X); string jiaodu = this.textBox1.Text; perAngle = int.Parse(jiaodu) * Math.PI / 180; nowAngle = startAngle + perAngle; xiedLength = (float)Math.Sqrt(Math.Pow(xiePointF.X - centerPoint.X， 2) + Math.Pow(xiePointF.Y - centerPoint.Y， 2)); xiedPointF.X = centerPoint.X - (float)(xiedLength * Math.Cos(nowAngle)); xiedPointF.Y = centerPoint.Y + (float)(xiedLength * Math.Sin(nowAngle)); xiePointFs1[index] = xiedPointF; } graphics.DrawCurve(pen， xiePointFs1， 1.5f); } private void button2_Click(object sender， EventArgs e)//倾斜角度，每次递减10度 { angle -= 10; this.textBox1.Text = angle.ToString(); if (this.textBox1.Text == "") { this.errorProvider1.SetError(this.textBox1， "请输入倾斜的角度"); return; } else { this.errorProvider1.SetError(this.textBox1， ""); } xyPoint.X = this.panel1.Width / 2-200; xyPoint.Y = this.panel1.Height / 2-100; centerPoint.X = xyPoint.X + a; centerPoint.Y = xyPoint.Y + b; Graphics graphics = this.panel1.CreateGraphics(); graphics.SmoothingMode = SmoothingMode.HighQuality; graphics.Clear(this.panel1.BackColor); Pen pen = new Pen(Color.Red); for (int index = 0; index < pointFs.Length; index++) { movePoint.X = index * stepLength + xyPoint.X; xLength = centerPoint.X - movePoint.X; yLength = (float)(Math.Sqrt((1 - (xLength * xLength) / 40000) * 10000)); movePoint.Y = b - yLength + xyPoint.Y; pointFs[index] = movePoint; } graphics.DrawCurve(pen， pointFs， 1.5f); for (int index = 0; index < pointFs1.Length; index++) { dbYlength = centerPoint.Y - pointFs[index].Y; pointFs1[index].Y = centerPoint.Y + dbYlength; pointFs1[index].X = pointFs[index].X; } graphics.DrawCurve(pen， pointFs1， 1.5f); for (int index = 0; index < pointFs.Length; index++) { xiePointF = pointFs[index]; double startAngle = Math.Atan2(xiePointF.Y - centerPoint.Y， xiePointF.X - centerPoint.X); string jiaodu = this.textBox1.Text; perAngle = int.Parse(jiaodu) * Math.PI / 180; nowAngle = startAngle + perAngle; xiedLength = (float)Math.Sqrt(Math.Pow(xiePointF.X - centerPoint.X， 2) + Math.Pow(xiePointF.Y - centerPoint.Y， 2)); xiedPointF.X = centerPoint.X - (float)(xiedLength * Math.Cos(nowAngle)); xiedPointF.Y = centerPoint.Y + (float)(xiedLength * Math.Sin(nowAngle)); xiePointFs[index] = xiedPointF; } graphics.DrawCurve(pen， xiePointFs， 1.5f); for (int index = 0; index < pointFs1.Length; index++) { xiePointF = pointFs1[index]; double startAngle = Math.Atan2(xiePointF.Y - centerPoint.Y， xiePointF.X - centerPoint.X); string jiaodu = this.textBox1.Text; perAngle = int.Parse(jiaodu) * Math.PI / 180; nowAngle = startAngle + perAngle; xiedLength = (float)Math.Sqrt(Math.Pow(xiePointF.X - centerPoint.X， 2) + Math.Pow(xiePointF.Y - centerPoint.Y， 2)); xiedPointF.X = centerPoint.X - (float)(xiedLength * Math.Cos(nowAngle)); xiedPointF.Y = centerPoint.Y + (float)(xiedLength * Math.Sin(nowAngle)); xiePointFs1[index] = xiedPointF; } graphics.DrawCurve(pen， xiePointFs1， 1.5f); } private void textBox1_TextChanged(object sender， EventArgs e)//输入倾斜的角度 { angle = int.Parse(this.textBox1.Text); } } }
