using System;
using System.Windows.Forms;

namespace DemoWinForm
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
    }

    /// <summary>
    /// 禁止粘貼
    /// </summary>
    public class TextBoxEx : TextBox
    {
        /// <summary>
        /// 構造函數
        /// </summary>
        public TextBoxEx()
        {
        }

        #region 禁止粘貼
        /// <summary>
        /// 重寫基類的WndProc方法
        /// </summary>
        /// <param name="m"></param>
        protected override void WndProc(ref Message m)
        {
            if (m.Msg == 0x0302)            // 0x0302是粘貼消息
            {
                m.Result = IntPtr.Zero;     // 攔截此消息
                return;
            }
            base.WndProc(ref m);            // 若此消息不是粘貼消息，則交給其基類去處理
        }
        #endregion
    }
}