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

namespace NewMyFormDesigner
{
    public partial class TextBoxEx : TextBox
    {
        private Color borderColor = Color.Black;   // 设置默认的边框颜色
        private static int WM_NCPAINT = 0x0085;    // WM_NCPAINT message
        private static int WM_ERASEBKGND = 0x0014; // WM_ERASEBKGND message
        private static int WM_PAINT = 0x000F;      // WM_PAINT message

        public TextBoxEx()
        {
            // This call is required by the Windows.Forms Form Designer.
            InitializeComponent();
            // TODO: Add any initialization after the InitializeComponent call
            this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);
            this.BackColor = Color.Transparent;

            this.SetStyle(ControlStyles.UserPaint, false);
            this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);
            this.SetStyle(ControlStyles.DoubleBuffer, true);


            
        }

        public void DrawBorder(ref Message message, int width, int height)
        {
            if (message.Msg == WM_NCPAINT || message.Msg == WM_ERASEBKGND ||
                message.Msg == WM_PAINT)
            {
                using (Graphics graphics = Graphics.FromHwnd(base.Handle))
                {
                    Rectangle rectangle = new Rectangle(0, 0, width, height);
                    ControlPaint.DrawBorder(graphics, rectangle,
                        Color.White, 0, ButtonBorderStyle.None,
                        Color.White, 0, ButtonBorderStyle.None,
                        Color.White, 0, ButtonBorderStyle.None,
                        BorderColor, 1, ButtonBorderStyle.Solid);
                }
            }
        }
        [Description("设置边框颜色")]
        public Color BorderColor
        {
            get { return borderColor; }
            set { borderColor = value; }
        }

        protected override void WndProc(ref Message m)
        {
            base.WndProc(ref m);
            DrawBorder(ref m, this.Width, this.Height);
        }

    }
}