原文:DevExpress Winform使用单例运行程序方法和非DevExpress使用Mutex实现程序单实例运行且运行则激活窗体的方法
版权声明：本文为博主原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接和本声明。
网上关于C#单例运行程序的方法都是比较简单，有些甚至是无法实现功能的，不知道他们试没试过就发帖，因为自己之前都是用第三方控件DevExpress，单例运行也是用它本身自带的一个方法，调用此方法需要引用DevExpress的DevExpress.DevAV.v17.1.Data.dll
-
static void Main()
-
{
-
var appName= Process.GetCurrentProcess().ProcessName;
-
using (DevExpress.Internal.DevAVDataDirectoryHelper.SingleInstanceApplicationGuard(appName, out exit))
-
{
-
if (exit)
-
return;
-
Application.EnableVisualStyles();
-
Application.SetCompatibleTextRenderingDefault(false);
-
Application.Run(new Form1());
-
}
-
}
以前懒，看到有现成的就拿现成的，也没去想具体如何实现，刚好有人问起，才决定去看看源码，发现DevExpress的这个方法原来是用了Mutex来实现的，整合了一下资料，重新写一个供C#桌面应用程序通用的单例运行方法，代码如下：
其中需要引用以下命名空间:
-
using System;
-
using System.Diagnostics;
-
using System.Drawing;
-
using System.Runtime.InteropServices;
-
using System.Security;
-
using System.Threading;
-
/// <summary>
-
/// 单实例应用程序--by涛神
-
/// </summary>
-
public class SingleInstanceApplication
-
{
-
/// <summary>
-
/// 判断应用是否运行
-
/// </summary>
-
/// <param name="processName"></param>
-
/// <param name="exit"></param>
-
/// <returns></returns>
-
public static IDisposable Guard(out bool exit)
-
{
-
Process currentProcess = Process.GetCurrentProcess();
-
var processName = currentProcess.ProcessName;
-
Mutex mutex = new Mutex(true, processName, out bool createNew);
-
if (createNew)
-
{
-
exit = false;
-
}
-
else
-
{
-
Process[] processesByName = Process.GetProcessesByName(currentProcess.ProcessName);
-
int num = 0;
-
while (num < (int)processesByName.Length)
-
{
-
Process process = processesByName[num];
-
if (process.Id == currentProcess.Id || !(process.MainWindowHandle != IntPtr.Zero))
-
{
-
num++;
-
}
-
else
-
{
-
WinApiHelper.SetForegroundWindow(process.MainWindowHandle);
-
WinApiHelper.RestoreWindowAsync(process.MainWindowHandle);
-
break;
-
}
-
}
-
exit = true;
-
}
-
return mutex;
-
}
-
private static class WinApiHelper
-
{
-
[SecuritySafeCritical]
-
public static bool IsMaxmimized(IntPtr hwnd)
-
{
-
WinApiHelper.Import.WINDOWPLACEMENT wINDOWPLACEMENT = new WinApiHelper.Import.WINDOWPLACEMENT();
-
if (!WinApiHelper.Import.GetWindowPlacement(hwnd, ref wINDOWPLACEMENT))
-
{
-
return false;
-
}
-
return wINDOWPLACEMENT.showCmd == WinApiHelper.Import.ShowWindowCommands.ShowMaximized;
-
}
-
-
[SecuritySafeCritical]
-
public static bool RestoreWindowAsync(IntPtr hwnd)
-
{
-
return WinApiHelper.Import.ShowWindowAsync(hwnd, (WinApiHelper.IsMaxmimized(hwnd) ? 3 : 9));
-
}
-
-
[SecuritySafeCritical]
-
public static bool SetForegroundWindow(IntPtr hwnd)
-
{
-
return WinApiHelper.Import.SetForegroundWindow(hwnd);
-
}
-
-
private static class Import
-
{
-
[DllImport("user32.dll", CharSet = CharSet.None, ExactSpelling = false)]
-
public static extern bool GetWindowPlacement(IntPtr hWnd, ref WinApiHelper.Import.WINDOWPLACEMENT lpwndpl);
-
-
[DllImport("user32.dll", CharSet = CharSet.None, ExactSpelling = false)]
-
public static extern bool SetForegroundWindow(IntPtr hWnd);
-
-
[DllImport("user32.dll", CharSet = CharSet.None, ExactSpelling = false)]
-
public static extern bool ShowWindowAsync(IntPtr hWnd, int nCmdShow);
-
-
public enum ShowWindowCommands
-
{
-
Hide,
-
Normal,
-
ShowMinimized,
-
ShowMaximized,
-
ShowNoActivate,
-
Show,
-
Minimize,
-
ShowMinNoActive,
-
ShowNA,
-
Restore,
-
ShowDefault,
-
ForceMinimize
-
}
-
-
public struct WINDOWPLACEMENT
-
{
-
public int length;
-
-
public int flags;
-
-
public WinApiHelper.Import.ShowWindowCommands showCmd;
-
-
public Point ptMinPosition;
-
-
public Point ptMaxPosition;
-
-
public Rectangle rcNormalPosition;
-
}
-
}
-
}
-
}
调用的demo如下，亲测可以，若无法实现的请留言讨论（本文章是原创文章，转载请标明，盗版必究，觉得文章对你帮助的可以点个赞表示支持一下，谢谢）：
-
static void Main()
-
{
-
using(SingleInstanceApplication.Guard(out bool exit))
-
{
-
if (exit)
-
return;
-
Application.EnableVisualStyles();
-
Application.SetCompatibleTextRenderingDefault(false);
-
Application.Run(new Form1());
-
}
-
}