C#之設置無邊框后如何移動窗體（轉）

轉載：http://www.cnblogs.com/techmango/archive/2012/03/31/2427523.html

 

第一種，利用windows的消息機制來實現：

首先﹐.定義鼠標左鍵按下時的Message標識﹔其次﹐在Form1_MouseDown方法﹐讓操作系統誤以為是按下標題欄。

1.定義鼠標左鍵按下時的Message標識

   private const int WM_NCLBUTTONDOWN = 0XA1;   //.定義鼠標左鍵按下
   private const int HTCAPTION     = 2;

2.讓操作系統誤以為是按下標題欄

private void Form1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
   {   
    //為當前的應用程序釋放鼠標鋪獲
    ReleaseCapture();
    //發送消息﹐讓系統誤以為在標題欄上按下鼠標
    SendMessage((int)this.Handle,WM_NCLBUTTONDOWN,HTCAPTION,0);
   }

3.申明程序中所Windows的API函數

   [DllImport("user32.dll",EntryPoint="SendMessageA")]
   private static extern int SendMessage(int hwnd,int wMsg,int wParam,int lParam);

   [DllImport("user32.dll")]
   private static extern int ReleaseCapture();

 

第二種，通過自定鼠標左鍵按下時產生的事件:

 * 首先將窗體的邊框樣式修改為None，讓窗體沒有標題欄
 * 實現這個效果使用了三個事件：鼠標按下、鼠標彈起、鼠標移動
 * 鼠標按下時更改變量isMouseDown標記窗體可以隨鼠標的移動而移動
 * 鼠標移動時根據鼠標的移動量更改窗體的location屬性，實現窗體移動
 * 鼠標彈起時更改變量isMouseDown標記窗體不可以隨鼠標的移動而移動
 */

private bool isMouseDown = false;
private Point FormLocation;     //form的location
private Point mouseOffset;      //鼠標的按下位置

 

private void Form1_MouseDown(object sender, MouseEventArgs e)
{
    if (e.Button == MouseButtons.Left)
    {
        isMouseDown = true;
        FormLocation = this.Location;
        mouseOffset = Control.MousePosition;
    }
}

 

private void Form1_MouseUp(object sender, MouseEventArgs e)
{
    isMouseDown = false;
}

 

private void Form1_MouseMove(object sender, MouseEventArgs e)
{
    int _x = 0;
    int _y = 0;
    if (isMouseDown)
    {
        Point pt = Control.MousePosition;
        _x = mouseOffset.X - pt.X;
        _y = mouseOffset.Y - pt.Y;

        this.Location = new Point(FormLocation.X - _x, FormLocation.Y - _y);
    }
}