鼠标拖动窗体代码

 1 private bool _mouseDown;
 2 private bool _busy;
 3 private int _downX;
 4 private int _downY;
 5
 6  private void lblTitle_MouseDown(object sender, MouseEventArgs e)
 7        {
 8            if (e.Button==MouseButtons.Left)
 9            {
10                if (!this._busy)
11                {
12                    try
13                    {
14                        this._busy = true;
15                        this._mouseDown = true;
16
17                        this._downX = e.X;
18                        this._downY = e.Y;
19                    }
20                    catch (Exception)
21                    {
22                        throw;
23                    }
24                    finally 
25                    {
26                        _busy = false;
27                    }
28                    
29                }
30                
31            }
32           
33        }
34        private void lblTitle_MouseEnter(object sender, EventArgs e)
35        {
36            this._mouseDown = false;
37        }
38        private void lblTitle_MouseLeave(object sender, EventArgs e)
39        {
40            this._mouseDown = false;
41        }
42        private void lblTitle_MouseMove(object sender, MouseEventArgs e)
43        {
44            if (this._mouseDown)
45            {
46                if (!_busy)
47                {
48                    try 
49                    {
50                        int offsetX = e.X - _downX;
51                        int offsetY = e.Y - _downY;
52
53                        this.Top += offsetY;
54                        this.Left += offsetX;
55                    }
56                    catch 
57                    {
58                        throw;
59                    }
60                    finally 
61                    {
62                        this._busy = false;
63                    }
64                }
65            }
66        }
67        private void lblTitle_MouseUp(object sender, MouseEventArgs e)
68        {
69            this._mouseDown = false;
70            this._busy = false;
71        }