SingleInstance.cs文件，
using System;
using System.IO;
using System.Diagnostics;
using System.Threading;
using System.Reflection;
using System.Runtime.InteropServices;
namespace Zhengzuo.CSharpCode
{
/// <summary>
/// 只启动一个应用程序实例控制类
/// </summary>
public static class SingleInstance
{
private const int WS_SHOWNORMAL = 1;
[DllImport("User32.dll")]
private static extern bool ShowWindowAsync(IntPtr hWnd, int cmdShow);
[DllImport("User32.dll")]
private static extern bool SetForegroundWindow(IntPtr hWnd);
//标志文件名称
private static string runFlagFullname = null;
//声明同步基元
private static Mutex mutex = null;
/// <summary>
/// static Constructor
/// </summary>
static SingleInstance()
{
}
#region api实现
/// <summary>
/// 获取应用程序进程实例,如果没有匹配进程，返回Null
/// </summary>
/// <returns>返回当前Process实例</returns>
public static Process GetRunningInstance()
{
Process currentProcess = Process.GetCurrentProcess();//获取当前进程
//获取当前运行程序完全限定名
string currentFileName = currentProcess.MainModule.FileName;
//获取进程名为ProcessName的Process数组。
Process[] processes = Process.GetProcessesByName(currentProcess.ProcessName);
//遍历有相同进程名称正在运行的进程
foreach (Process process in processes)
{
if (process.MainModule.FileName == currentFileName)
{
if (process.Id != currentProcess.Id)//根据进程ID排除当前进程
return process;//返回已运行的进程实例
}
}
return null;
}
/// <summary>
/// 获取应用程序句柄，设置应用程序前台运行，并返回bool值
/// </summary>
public static bool HandleRunningInstance(Process instance)
{
//确保窗口没有被最小化或最大化
ShowWindowAsync(instance.MainWindowHandle, WS_SHOWNORMAL);
//设置真实例程为foreground window
return SetForegroundWindow(instance.MainWindowHandle);
}
/// <summary>
/// 获取窗口句柄，设置应用程序前台运行，并返回bool值，重载方法
/// </summary>
/// <returns></returns>
public static bool HandleRunningInstance()
{
Process p = GetRunningInstance();
if (p != null)
{
HandleRunningInstance(p);
return true;
}
return false;
}
#endregion
#region Mutex实现
/// <summary>
/// 创建应用程序进程Mutex
/// </summary>
/// <returns>返回创建结果，true表示创建成功，false创建失败。</returns>
public static bool CreateMutex()
{
return CreateMutex(Assembly.GetEntryAssembly().FullName);
}
/// <summary>
/// 创建应用程序进程Mutex
/// </summary>
/// <param name="name">Mutex名称</param>
/// <returns>返回创建结果，true表示创建成功，false创建失败。</returns>
public static bool CreateMutex(string name)
{
bool result = false;
mutex = new Mutex(true, name, out result);
return result;
}
/// <summary>
/// 释放Mutex
/// </summary>
public static void ReleaseMutex()
{
if (mutex != null)
{
mutex.Close();
}
}
#endregion
#region 设置标志实现
/// <summary>
/// 初始化程序运行标志，如果设置成功，返回true，已经设置返回false，设置失败将抛出异常
/// </summary>
/// <returns>返回设置结果</returns>
public static bool InitRunFlag()
{
if (File.Exists(RunFlag))
{
return false;
}
using (FileStream fs = new FileStream(RunFlag, FileMode.Create))
{
}
return true;
}
/// <summary>
/// 释放初始化程序运行标志，如果释放失败将抛出异常
/// </summary>
public static void DisposeRunFlag()
{
if (File.Exists(RunFlag))
{
File.Delete(RunFlag);
}
}
/// <summary>
/// 获取或设置程序运行标志，必须符合Windows文件命名规范
/// 这里实现生成临时文件为依据，如果修改成设置注册表，那就不需要符合文件命名规范。
/// </summary>
public static string RunFlag
{
get
{
if(runFlagFullname == null)
{
string assemblyFullName = Assembly.GetEntryAssembly().FullName;
//CommonApplicationData：//"C:\\Documents and Settings\\All Users\\Application Data"
string path = Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData);
//"C:\\Program Files\\Common Files"
//string path = Environment.GetFolderPath(Environment.SpecialFolder.CommonProgramFiles);
runFlagFullname = Path.Combine(path, assemblyFullName);
}
return runFlagFullname;
}
set
{
runFlagFullname = value;
}
}
#endregion
}
}
Program.cs文件，
using System;
using System.Windows.Forms;
using System.Diagnostics;
using Zhengzuo.CSharpCode;
namespace Zhengzuo.Test.WinGui
{
static class Program
{
[STAThread]
static void Main(string[] args)
{
if (args.Length == 0) //没有传送参数
{
Process p = SingleInstance.GetRunningInstance();
if (p != null) //已经有应用程序副本执行
{
SingleInstance.HandleRunningInstance(p);
}
else //启动第一个应用程序
{
RunApplication();
}
}
else //有多个参数
{
switch (args[0].ToLower())
{
case "-api":
if (SingleInstance.HandleRunningInstance() == false)
{
RunApplication();
}
break;
case "-mutex":
if (args.Length >= 2) //参数中传入互斥体名称
{
if ( SingleInstance.CreateMutex(args[1]) )
{
RunApplication();
SingleInstance.ReleaseMutex();
}
else
{
//调用SingleInstance.HandleRunningInstance()方法显示到前台。
MessageBox.Show("程序已经运行！");
}
}
else
{
if (SingleInstance.CreateMutex())
{
RunApplication();
SingleInstance.ReleaseMutex();
}
else
{
//调用SingleInstance.HandleRunningInstance()方法显示到前台。
MessageBox.Show("程序已经运行！");
}
}
break;
case "-flag"://使用该方式需要在程序退出时调用
if (args.Length >= 2) //参数中传入运行标志文件名称
{
SingleInstance.RunFlag = args[1];
}
try
{
if (SingleInstance.InitRunFlag())
{
RunApplication();
SingleInstance.DisposeRunFlag();
}
else
{
//调用SingleInstance.HandleRunningInstance()方法显示到前台。
MessageBox.Show("程序已经运行！");
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
break;
default:
MessageBox.Show("应用程序参数设置失败。");
break;
}
}
}
//启动应用程序
static void RunApplication()
{
Application.EnableVisualStyles();
Application.Run(new MainForm());
}
}
}