C# FormBorderStyle設置爲none時可拖動Form

 bool formMove = false;//窗體是否移動
        Point formPoint;//記錄窗體的位置  
         private void Form1_MouseDown(object sender, MouseEventArgs e)
         {
            formPoint = new Point();        
            int xOffset;          
            int yOffset;         
            if (e.Button == MouseButtons.Left)       
             {
                xOffset = -e.X;
                yOffset = -e.Y;
                formPoint = new Point(xOffset, yOffset);
                formMove = true;//開始移動  
            }
         }
         private void Form1_MouseMove(object sender, MouseEventArgs e)
         {
            if (formMove == true)
             {
                 Point mousePos = Control.MousePosition;
                 mousePos.Offset(formPoint.X, formPoint.Y);
                 Location = mousePos;
             }
         }
        private void Form1_MouseUp(object sender, MouseEventArgs e)
         {
            if (e.Button == MouseButtons.Left)//按下的是鼠標左鍵    
            {
                formMove = false;//停止移動        
            }
        }