1. 重写WndProc
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protected override void WndProc(ref Message m) { const int WM_NCHITTEST = 0x84; const int HTCLIENT = 0x01; const int HTCAPTION = 0x02; if (m.Msg == WM_NCHITTEST) { this.DefWndProc(ref m); if (m.Result.ToInt32() == HTCLIENT) m.Result = new IntPtr(HTCAPTION); else base.WndProc(ref m); } else { base.WndProc(ref m); } }
2.创建消息
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private const int WM_NCLBUTTONDOWN = 0x00A1; private const int WM_NCHITTEST = 0x84; private const int HT_CAPTION = 0x2; private const int HT_CLIENT = 0x1; private void pictureBox1_MouseDown(object sender, MouseEventArgs e) { //this.Capture = false; pictureBox1.Capture = false; Message msg = Message.Create(Handle, WM_NCLBUTTONDOWN, (IntPtr)HT_CAPTION, IntPtr.Zero); WndProc(ref msg); }
3.调用API代码
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using System.Runtime.InteropServices; [DllImport("user32.dll")] 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; //在窗体的_MouseDown中加入如下代码: 如: private void Form1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e) { ReleaseCapture(); SendMessage(this.Handle, WM_SYSCOMMAND, SC_MOVE + HTCAPTION, 0); }