不允许在textBox里粘贴

namespace 不允许在textBox里粘贴
{
    public partial class loginForm : Form
    {
        public loginForm()
        {
            InitializeComponent();
        }
        private Point offset;

        private void panel1_MouseDown(object sender, MouseEventArgs e)
        {
            if (MouseButtons.Left != e.Button) return;

            Point cur = this.PointToScreen(e.Location);
            offset = new Point(cur.X - this.Left, cur.Y - this.Top);
        }

        private void panel1_MouseMove(object sender, MouseEventArgs e)
        {
            if (MouseButtons.Left != e.Button) return;
            Point cur = MousePosition;
            this.Location = new Point(cur.X - offset.X, cur.Y - offset.Y);
        }

        private void loginForm_Load(object sender, EventArgs e)
        {

        }

        private void btlCloseButton_Click(object sender, EventArgs e)
        {
            System.Windows.Forms.Application.Exit();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (textBox1.Text!=""){  //要注意.Text，需要大写
               
            };

        }


      
    }


}

    class TextBoxx : TextBox
    {
        public const int WM_PASTE = 0x0302;//粘贴消息信息
        protected override void WndProc(ref Message m)//重写处理消息方法
        {
            if (m.Msg != WM_PASTE)//屏蔽粘贴消息信息
            {
                base.WndProc(ref m);//调用基类消息处理方法
            }
        }
    }