本文汇总了几个WinForm中常见的实用技巧，对于C#程序开发有着很好的参考借鉴价值。具体分析如下：

一、屏蔽窗体右上角关闭按钮

1.重写OnClosing

protected override void OnClosing(CancelEventArgs e) { if(this.Visible) { e.Cancel=true; // // WHATE TODO // } }

2.重写WndProc

protected override void WndProc(ref Message m) { const int WM_SYSCOMMAND = 0x0112; const int SC_CLOSE = 0xF060; if (m.Msg == WM_SYSCOMMAND && (int) m.WParam == SC_CLOSE) { // User clicked close button this.WindowState = FormWindowState.Minimized; return; } base.WndProc(ref m); }

更多方法可以参考：

http://topic.csdn.net/u/20091220/21/5228d0d6-26aa-48b8-81aa-293f7c7339f8.html?94449

http://topic.csdn.net/u/20090419/18/970d8ad9-ed9a-4bd9-a623-81d23106545b.html

二、屏蔽CTRL-V

在WinForm中的TextBox控件没有办法屏蔽CTRL-V的剪贴板粘贴动作，如果需要一个输入框，但是不希望用户粘贴剪贴板的内容，可以改用RichTextBox控件，并且在KeyDown中屏蔽掉CTRL-V键，例子：

private void richTextBox1_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e) { if(e.Control && e.KeyCode==Keys.V) e.Handled = true; }

三、应用程序单例运行

#region 单实例运行 /// <summary> /// 单实例运行 /// </summary> /// <param name="frm">所要运行的主窗体</param> public static void SingleRun(Form frm) { System.Threading.Mutex mutex = new System.Threading.Mutex(false,"SINGLE_INSTANCE_MUTEX"); if (!mutex.WaitOne(0, false)) { mutex.Close(); mutex = null; } if (mutex != null) { Application.Run(frm); } else { MessageBox.Show("应用程序已启动","信息提示",MessageBoxButtons.OK,MessageBoxIcon.Information); } } #endregion

四、将控件转换成圆形

#region 将控件转换为圆形 [System.Runtime.InteropServices.DllImport("gdi32")] private static extern IntPtr BeginPath(IntPtr hdc); [System.Runtime.InteropServices.DllImport("gdi32")] private static extern int SetBkMode(IntPtr hdc,int nBkMode); const int TRANSPARENT=1; [System.Runtime.InteropServices.DllImport("gdi32")] private static extern IntPtr EndPath(IntPtr hdc); [System.Runtime.InteropServices.DllImport("gdi32")] private static extern IntPtr PathToRegion(IntPtr hdc); [System.Runtime.InteropServices.DllImport("gdi32")] private static extern int Ellipse(IntPtr hdc,int x1,int y1,int x2,int y2); [System.Runtime.InteropServices.DllImport("user32")] private static extern IntPtr SetWindowRgn(IntPtr hwnd,IntPtr hRgn,bool bRedraw); [System.Runtime.InteropServices.DllImport("user32")] private static extern IntPtr GetDC(IntPtr hwnd); /// <summary> /// 将控件转为圆形 /// </summary> /// <param name="control">控件名</param> public static void MakeControlToCircle(Control[] control) { IntPtr dc; IntPtr region; for(int i=0;i<control.Length;i++) { dc=GetDC(control[i].Handle); BeginPath(dc); SetBkMode(dc,TRANSPARENT); Ellipse(dc,0,0,control[i].Width-3,control[i].Height-2); EndPath(dc); region=PathToRegion(dc); SetWindowRgn(control[i].Handle,region,false); } } #endregion

五、在同一应用程序中同一窗体只打开一个

/// <summary> /// 在同一应用程序中同一窗体只打开一个 /// </summary> /// <param name="frmOpen">要打开的窗体实例</param> /// <returns></returns> public static void OpenSeamForm(Form frmOpen) { foreach (Form frm in Application.OpenForms) { if (frm.Text == frmOpen.Text) { frm.Visible = true; frm.WindowState = FormWindowState.Normal; frm.Activate(); return; } } frmOpen.Show(); }

相信本文所述实例对大家WinForm程序设计可以带来很大帮助。