C# 单进程实例

static class Program { /// <summary> /// 应用程序的主入口点。 /// </summary> [STAThread] static void Main() { bool isAppRunning = false; System.Threading.Mutex mutex = new System.Threading.Mutex( true, Assembly.GetExecutingAssembly().FullName, out isAppRunning); if (!isAppRunning) { MessageBox.Show("本程序已经有一个实例在运行了!", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); Environment.Exit(1); } else { Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); Application.Run(new ServerMainForm()); } } } /// <summary>
/// 应用程序的主入口点。
/// </summary>
[STAThread]
static void Main()
{
Process instance=RunningInstance();
if(instance==null)
{
//没有实例在运行
Application.Run(new Form1());
}
else
{
//已经有一个实例在运行
HandleRunningInstance(instance);
}
}
#region 确保程序只运行一个实例
private static Process RunningInstance()
{
Process current=Process.GetCurrentProcess();
Process[] processes=Process.GetProcessesByName(current.ProcessName);
//遍历与当前进程名称相同的进程列表
foreach(Process process in processes)
{
//如果实例已经存在则忽略当前进程
if(process.Id!=current.Id)
{
//保证要打开的进程同已经存在的进程来自同一文件路径
if(Assembly.GetExecutingAssembly().Location.Replace("/","//")==current.MainModule.FileName)
{
//返回已经存在的进程
return process;
}
}
}
return null;
}

private static void HandleRunningInstance(Process instance)
{
MessageBox.Show("监控系统已经在运行！","提示信息",MessageBoxButtons.OK,MessageBoxIcon.Information);
ShowWindowAsync(instance.MainWindowHandle,1); //调用api函数，正常显示窗口
SetForegroundWindow(instance.MainWindowHandle); //将窗口放置最前端
}
[DllImport("User32.dll")]
private static extern bool ShowWindowAsync(System.IntPtr hWnd,int cmdShow);
[DllImport("User32.dll")]
private static extern bool SetForegroundWindow(System.IntPtr hWnd);
#endregion