请教：允许程序只运行一个实例，内容如下
怎样允许程序只运行一个实例，看了很多都只能打开程序本身才可以，如果用文档关联程序的方式打开还是不行。记住我要的是后面那种情况

[解决办法]

Delphi(Pascal) code

var hMutex:HWND;begin  hMutex:=CreateMutex(nil,false,'CYGL');//关键这个句柄，你说的那种情况应该是动态的生成句柄吧  if WaitForSingleObject(hMutex,0)<>wait_TimeOut then  begin  Application.Initialize;  Application.CreateForm(TForm1, Form1);  Application.Run;  end    else  begin  messagebox(hmutex,'程序已经存在，不能重复运行！','系统信息',$00000040);  hmutex:=findwindow(nil,'CYGL');  SetForeGroundWindow(hmutex);  SetActiveWindow(hmutex);  halt;  end;end.
[解决办法]
Delphi(Pascal) code
var  vSnapshot: THandle;  vProcessEntry32: TProcessEntry32;  vExeName: string;  vProcessWindowInfo: TProcessWindowInfo;begin  ///////Begin 检查是否已经开启了程序               vExeName := ExtractFileName(ParamStr(0));  vSnapshot := CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);  try    vProcessEntry32.dwSize := SizeOf(TProcessEntry32);    if Process32First(vSnapshot, vProcessEntry32) then      repeat        if (vProcessEntry32.th32ProcessID <> GetCurrentProcessId) and          SameText(ExtractFileName(vProcessEntry32.szExeFile), vExeName) then        begin          vProcessWindowInfo.rProcessID := vProcessEntry32.th32ProcessID;          vProcessWindowInfo.rWindowClass := 'TfrmWebClient';          vProcessWindowInfo.rWindowHandle := 0;          EnumWindows(@EnumWindowsProc, Integer(@vProcessWindowInfo));          if vProcessWindowInfo.rWindowHandle <> 0 then Exit;        end;      until not Process32Next(vSnapshot, vProcessEntry32);  finally    CloseHandle(vSnapshot);  end;  ///////End 检查是否已经开启了程序
[解决办法]
在工程 的dpr文件中加入：

Delphi(Pascal) code
var  hMutex: THandle;begin  Application.Initialize;  hMutex := OpenMutex(SYNCHRONIZE, False, 'AAAMutex');  if hMutex <> 0 then  begin    CloseHandle(hMutex);    Application.MessageBox('系统只允许同时运行一个程序', '系统提示', MB_ICONERROR);    Exit;  end;  hMutex := CreateMutex(nil, True, 'AAAMutex');     Application.CreateForm(TfmMain, fmMain);      end .
[解决办法]
program Project1;

uses
 Windows, Forms,
 Unit1 in 'Unit1.pas' {Form1};

{$R *.RES}

begin
 Application.Initialize;

   Application.Title:='我的测试程序';
   CreateMutex(nil,False,'我的测试程序');
   if(GetLastError()=ERROR_ALREADY_EXISTS)then exit;

 Application.CreateForm(TForm1, Form1);
 Application.Run;
end.
这个肯定没有问题的,
测试环境:D7+WINSP3
楼主给分吧..........