Winform GDI+自定义LED指示灯控件

1.新建一个类库
2.添加用户控件
3.在用户窗体写代码

点击查看代码

namespace MyControls
{
    public partial class LED : UserControl
    {
        public LED()
        {
            InitializeComponent();
            //添加事件
            this.Paint += LED_Paint;
        }
        //圆颜色
        private Color _roundColor = Color.Gray;

        [Category("自定义属性")]
        [Description("圆颜色")]
        public Color RoundColor
        {
            get { return _roundColor; }
            set 
            {
                _roundColor = value;
                this.Invalidate();  
            }
        }

        //圆环颜色
        private Color _ringColor = Color.White;

        [Category("自定义属性")]
        [Description("圆环颜色")]
        public Color RingColor
        {
            get { return _ringColor; }
            set
            {
                _ringColor = value;
                this.Invalidate();
            }
        }

        //圆环距离
        private int _distance = 2;

        [Category("自定义属性")]
        [Description("圆环距离")]
        public int Distance
        {
            get { return _distance; }
            set
            {
                _distance = value;
                this.Invalidate();
            }
        }

        //圆环宽度
        private float _ringWidth = 1.0f;

        [Category("自定义属性")]
        [Description("圆环宽度")]
        public float RingWidth
        {
            get { return _ringWidth; }
            set 
            {   _ringWidth = value; 
                this.Invalidate();
            }
        }


        private void LED_Paint(object sender, PaintEventArgs e)
        {
            //获取画布
            Graphics g = e.Graphics;

            // 启用抗锯齿以获得更平滑的边缘
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;

            //获取圆画刷
            SolidBrush solidBrush = new SolidBrush(_roundColor);

            //获取圆矩形
            Rectangle rectangle = new Rectangle(1,1,this.Width - 2,this.Height - 2);

            //绘制椭圆
            g.FillEllipse(solidBrush, rectangle);

            //获取圆环画笔
            Pen pen = new Pen(_ringColor, _ringWidth);

            //获取圆环矩形
            RectangleF rectangleF = new RectangleF(_distance + 1 + _ringWidth / 2, _distance + 1 + _ringWidth / 2, this.Width - (_distance * 2) - 2 - _ringWidth, this.Height - (_distance * 2) - 2 - _ringWidth);
            
            //绘制圆环
            g.DrawEllipse(pen, rectangleF);
        }
    }
}

图片效果如下：