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在Delphi应用程序中打开的互斥锁已签入C控制台应用程序

delphi-10.1-berlin c#-4.0 delphi .net c#

RBA · 技术社区 · 7 年前

var
  AMutex: THandle;

function OpenMutex(const AMutexName: String): Boolean;
begin

  { Assume the Windows Mutext is already open }
  Result := False;

  { Is the Mutex already open? }
  if AMutex <> 0 then
    exit;

  { Try to create Windows Mutex }
  if CreateProgramMutex( AMutexName , AMutex) then
    Result := True
  else
    AMutex := 0;
end;

 function CreateProgramMutex( AMutexName: string; var AMutex: THandle ): boolean;
begin
    { Assume the new program mutex was created successfully. }
    Result := true;

    { Attempt to create a new mutex. }
    AMutex := CreateMutex(nil, False, PChar(AMutexName));

    { If we at least got a handle to the mutex... }
    if (AMutex <> 0) then
    begin

      if GetLastError = ERROR_ALREADY_EXISTS then begin
        { Close the handle, since it already exists. }
        CloseHandle(AMutex);

        { Set the return to show that it was already running. }
        Result := false;
      end;
    end else
      Result := false;
end;

我正在试着从C(作为初学者)了解我的应用程序是否已经在控制台应用程序中运行:

using System;
using System.Threading;

namespace ConsoleApplication1
{
    class OneAtATimePlease
    {
        private static Mutex _mutex;

        private static bool IsSingleInstance()
        {
            _mutex = new Mutex(false, "my mutex name");

            // keep the mutex reference alive until the normal 
            //termination of the program
            GC.KeepAlive(_mutex);

            try
            {
                return _mutex.WaitOne(0, false);
            }
            catch (AbandonedMutexException)
            {
                // if one thread acquires a Mutex object 
                //that another thread has abandoned 
                //by exiting without releasing it

                _mutex.ReleaseMutex();
                return _mutex.WaitOne(0, false);
            }
        }
        static void Main()
        {
            if (!IsSingleInstance())
                Console.WriteLine("already running");
            Console.ReadLine();

        }
    }
}

PS:一切都是在同一个Windows用户会话下完成的

2 回复 | 直到 7 年前

Victoria zac 7 年前

您说您的目标是检查一个外部应用程序是否正在运行(通过使用一个命名的互斥体)。对于这种情况,您不应该尝试在应用程序中创建具有给定名称的互斥对象,而应该只尝试打开这样的对象。原因很简单,如果外部应用程序使用这种互斥来检查它是否自己运行,那么实际上这个互斥对象用于应用程序,而这个外部互斥对象永远不会启动。

TryOpenExisting

using System;
using System.Threading;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            Mutex mutex;

            if (Mutex.TryOpenExisting("My unique mutex name", out mutex)) {
                try {
                    // with the used TryOpenExisting overload you can work with
                    // the mutex object here; you can wait for it or release
                    Console.WriteLine("Application is running!");
                }
                finally {
                    mutex.Close();
                }
            }
            else {
                Console.WriteLine("Application is NOT running!");
            }
            Console.ReadLine();
        }
    }
}

Ross Bush 7 年前

Mutex appMutex = new Mutex(true, "MyMutex", out exclusive);
if (!exclusive)
{
  //Instance already existed
}