1 using System;  2 using System.Collections.Generic;  3 using System.ComponentModel;  4 using System.Data;  5 using System.Drawing;  6 using System.Linq;  7 using System.Text;  8 using System.Windows.Forms;  9 using System.Runtime.InteropServices; 10  11 namespace WindowsFormsApplication2 12 { 13     public partial class Form1 : Form 14     { 15         public Form1() 16         { 17             InitializeComponent(); 18             this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None; 19         } 20  21         protected override void OnMouseDown(MouseEventArgs e) 22         { 23             base.OnMouseDown(e); 24             if (e.Button == MouseButtons.Left && 25                 this.WindowState != FormWindowState.Maximized) 26             { 27                 ReleaseCapture(); 28                 SendMessage(this.Handle, 274, 61440 + 9, 0); 29             } 30         } 31  32         [DllImport("user32.dll")] 33         public static extern int ReleaseCapture(); 34  35         [DllImport("user32.dll")] 36         public static extern int SendMessage(IntPtr hwnd, int msg, int up, int lp); 37  38         protected override void WndProc(ref Message m) 39         { 40             switch (m.Msg) 41             { 42                 case (int)WindowsMessage.WM_NCHITTEST: 43                     this.WM_NCHITTEST(ref m); 44                     break; 45                 default: 46                     base.WndProc(ref m); 47                     break; 48             } 49         } 50  51         public static int LOWORD(int value) 52         { 53             return value & 0xFFFF; 54         } 55  56         public static int HIWORD(int value) 57         { 58             return value >> 16; 59         } 60  61         private void WM_NCHITTEST(ref Message m) 62         { 63             int wparam = m.LParam.ToInt32(); 64             Point point = new Point(LOWORD(wparam), HIWORD(wparam)); 65             point = this.PointToClient(point); 66  67             if (point.X <= 5) 68             { 69                 if (point.Y <= 5) 70                     m.Result = (IntPtr)WinAPIConst.HTTOPLEFT; 71                 else if (point.Y > this.Height - 5) 72                     m.Result = (IntPtr)WinAPIConst.HTBOTTOMLEFT; 73                 else 74                     m.Result = (IntPtr)WinAPIConst.HTLEFT; 75             } 76             else if (point.X >= this.Width - 5) 77             { 78                 if (point.Y <= 5) 79                     m.Result = (IntPtr)WinAPIConst.HTTOPRIGHT; 80                 else if (point.Y >= this.Height - 5) 81                     m.Result = (IntPtr)WinAPIConst.HTBOTTOMRIGHT; 82                 else 83                     m.Result = (IntPtr)WinAPIConst.HTRIGHT; 84             } 85             else if (point.Y <= 5) 86             { 87                 m.Result = (IntPtr)WinAPIConst.HTTOP; 88             } 89             else if (point.Y >= this.Height - 5) 90             { 91                 m.Result = (IntPtr)WinAPIConst.HTBOTTOM; 92             } 93             else 94                 base.WndProc(ref m); 95         } 96     } 97  98     public enum WindowsMessage 99     {100         /// 
101         /// 移动鼠标，桉树或释放鼠标时发生102         /// 
103         WM_NCHITTEST = 0x84,104     }105     public class WinAPIConst106     {107         public const int HTLEFT = 10;108         public const int HTRIGHT = 11;109         public const int HTTOP = 12;110         public const int HTTOPLEFT = 13;111         public const int HTTOPRIGHT = 14;112         public const int HTBOTTOM = 15;113         public const int HTBOTTOMLEFT = 0x10;//16114         public const int HTBOTTOMRIGHT = 17;115         public const int HTCAPTION = 2;116 117     }118 }