Aotecar-CAN/CompressorXN_ControlLib/GroupBoxEx.cs

using System.ComponentModel;
using System.Drawing;
using System.Windows.Forms;

namespace CompressorXN_ControlLib
{
    public partial class GroupBoxEx : GroupBox
    {
        public GroupBoxEx()
        {
            InitializeComponent();

            this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);
            this.SetStyle(ControlStyles.DoubleBuffer, true);
            this.SetStyle(ControlStyles.ResizeRedraw, true);
            this.SetStyle(ControlStyles.Selectable, true);
            this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);
        }

        /// <summary>
        /// 边框颜色
        /// </summary>
        private Color _BorderColor = Color.Silver;

        [Browsable(true), Description("边框颜色"), Category("自定义属性")]
        public Color BorderColor
        {
            get { return _BorderColor; }
            set
            {
                _BorderColor = value;
                this.Invalidate();
            }
        }

        /// <summary>
        /// 重写Onpaint
        /// </summary>
        /// <param name="e"></param>
        protected override void OnPaint(PaintEventArgs e)
        {
            var vSize = e.Graphics.MeasureString(this.Text, this.Font);

            e.Graphics.Clear(this.BackColor);
            e.Graphics.DrawString(this.Text, this.Font, new SolidBrush(this.ForeColor), 10, 1);
            Pen vPen = new Pen(this._BorderColor);
            e.Graphics.DrawLine(vPen, 1, vSize.Height / 2, 8, vSize.Height / 2);
            e.Graphics.DrawLine(vPen, vSize.Width + 8, vSize.Height / 2, this.Width - 2, vSize.Height / 2);
            e.Graphics.DrawLine(vPen, 1, vSize.Height / 2, 1, this.Height - 2);
            e.Graphics.DrawLine(vPen, 1, this.Height - 2, this.Width - 2, this.Height - 2);
            e.Graphics.DrawLine(vPen, this.Width - 2, vSize.Height / 2, this.Width - 2, this.Height - 2);
        }
    }
}