C#中实现拖动无边框窗体Form

 Point mouseOff;//鼠标移动位置变量
            bool leftFlag;//标签是否为左键
            private void Form1_MouseDown(object sender, MouseEventArgs e)
            {
                if (e.Button == MouseButtons.Left)
                {
                    mouseOff = new Point(-e.X, -e.Y); //得到变量的值
                    leftFlag = true;                  //点击左键按下时标注为true;
                }
            }

            private void Form1_MouseMove(object sender, MouseEventArgs e)
            {
                if (leftFlag)
                {
                    Point mouseSet = Control.MousePosition;
                    mouseSet.Offset(mouseOff.X, mouseOff.Y);  //设置移动后的位置
                    Location = mouseSet;
                }
            }

            private void Form1_MouseUp(object sender, MouseEventArgs e)
            {
                if (leftFlag)
                {
                    leftFlag = false;//释放鼠标后标注为false;
                }
            }

第二种方法实现

[DllImport("user32.dll")]//*********************拖动无窗体的控件
 public static extern bool ReleaseCapture();
 [DllImport("user32.dll")]
 public static extern bool SendMessage(IntPtr hwnd, int wMsg, int wParam, int lParam);
 public const int WM_SYSCOMMAND = 0x0112;
 public const int SC_MOVE = 0xF010;
 public const int HTCAPTION = 0x0002;
 

下面再你要拖动触发的控件里面写上这句话

private void gPanelTitleBack_MouseDown(object sender, MouseEventArgs e)
 {
 ReleaseCapture();
 SendMessage(this.Handle, WM_SYSCOMMAND, SC_MOVE + HTCAPTION, 0);//*********************调用移动无窗体控件函数
 }