C#中自定义方向盘控件

因项目要求需要有方向盘的绘制，查了好多，决定自己画一个，虽然样式一般，但基本实现功能

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace XXX //自己的项目名称
{
    public partial class MyJoystick : Control
    {
        private float radius; 
        private PointF center;
        private Color frameColor = Color.FromArgb(18, 150, 219);
        private SolidBrush blackBrush = new SolidBrush(Color.FromArgb(18, 150, 219));
        private SolidBrush circleColor = new SolidBrush(Color.FromArgb(20, 20, 20));
        private float angle = 0;


        private Pen penFrame = null;  //边框画笔

        /// <summary>
        /// 角度值
        /// </summary>
        [Description("方向盘转动角度"), Category("自定义")]
        public float Angle
        {
            get { return this.angle; }
            set
            {            
                this.angle = value;
                this.Invalidate();
            }
        }

        /// <summary>
        /// 边框颜色
        /// </summary>
        [Description("方向盘边框颜色"), Category("自定义")]
        public Color FrameColor
        {
            get { return this.frameColor; }
            set
            {
                this.frameColor = value;
                this.penFrame.Color = value;
                this.Invalidate();
            }
        }


        //解决控件批量更新时带来的闪烁
        protected override CreateParams CreateParams { get { CreateParams cp = base.CreateParams; cp.ExStyle |= 0x02000000; return cp; } }


        public MyJoystick()
        {
            InitializeComponent();
            //初始化变量
            this.penFrame = new Pen(this.frameColor, 6);
            this.radius = this.Width/2;

        }


        protected override void OnPaint(PaintEventArgs e)
        {
            DrawJoystick(e.Graphics);
        }

        private void DrawJoystick(Graphics g)
        {
            if (this.Width < 50 || this.Height < 50)
            {
                return;
            }


            //双缓冲
            //在内存中建立一块“虚拟画布”
            Bitmap bmp = new Bitmap(this.Width, this.Height);
            //获取这块内存画布的Graphics引用
            g = Graphics.FromImage(bmp);

            //在这块内存画布上绘图
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
            //g.Clear(this.BackColor);

            //圆的大小
            int size = Math.Min(this.Width, this.Height);//圆的大小
            center = new PointF(size / 2, size / 2);

            //draw frame                      
            int sizeOffset =6;//距离最外侧的偏移量
            Rectangle rectangle = new Rectangle(this.Width / 2 - size / 2 + sizeOffset, this.Height / 2 - size / 2 + sizeOffset, size - (sizeOffset * 2), size - (sizeOffset * 2));//计算圆的范围
            g.DrawArc(this.penFrame, rectangle, 0, 360);//绘制外环


            //draw direction
            int nLine1 = size / 2 - sizeOffset;
            
            float nCenterLineX = center.X;  //中心点X
            float nCenterLineY = center.Y;  //中心点Y

            float x_start = nCenterLineX + (float)(nLine1) * (float)Math.Cos(Math.PI / 180 * angle);
            float y_start = nCenterLineY + (float)(nLine1) * (float)Math.Sin(Math.PI / 180 * angle);

            PointF p1 = new PointF(x_start, y_start);
            PointF p2 = new PointF((2 * nCenterLineX - p1.X), (2 * (nCenterLineY) - p1.Y));

            Pen mRed = new Pen(frameColor, 10);
            g.DrawLine(mRed, p1, p2);

            int nLine2 = size / 3;     //指针底边直径
            int nLineC = -size / 2;    //指针底边距中心Y轴的距离


            float nCenterLineXX = (float)((center.X) - (nLine1) * Math.Sin(Math.PI / 180 * angle)); //起点指针顶点X
            float nCenterLineYY = (float)((center.Y) + (nLine1) * Math.Cos(Math.PI / 180 * angle)); //起点指针顶点Y


            PointF p3 = new PointF(nCenterLineXX, nCenterLineYY);//起点指针顶点
            float x_start4 = (float)((nCenterLineX) - (nLine2 / 2) * Math.Cos(Math.PI / 180 * (-angle)));
            float y_start4 = (float)((nCenterLineY) + (nLine2 / 2) * Math.Sin(Math.PI / 180 * (-angle)));


            PointF p4 = new PointF(x_start4, y_start4);
            float x_end4 = (float)((2 * nCenterLineX - x_start4));
            float y_end4 = (float)((2 * (nCenterLineY) - y_start4));

            PointF p5 = new PointF(x_end4, y_end4);

            g.DrawLine(mRed, p4, p5);
            g.DrawLine(mRed, p3, p5);
            g.DrawLine(mRed, p3, p4);
            PointF[] pointss = { p3, p4, p5 };

            g.FillPolygon(blackBrush, pointss);//填充区域
            g.FillPie(circleColor, center.X - 5, center.Y - 5, 10, 10, 0, 360);//中心圆   

            //将内存画布画到窗口中
            this.CreateGraphics().DrawImage(bmp, 0, 0);

            g.Dispose();
            bmp.Dispose();
        }

    }
}

在自己的项目中点击右键，选择添加 -> 选择新建项 -> 选择组件类，定义自己的控件名，然后复制本代码就可以了。

 然后点击生成解决方案后，就可以在工具内找到自己定义的控件了

 制作效果如下：

赋值的话，直接用控件名.Angle = value;就可以了

注意：此自定义控件有一个小bug，拖拽出来的控件得为正方形才可以，以后有机会再继续改进

转载需要标注转载地址哦~~~