如何判断程序是否运行？

Question

如何判断程序是否运行？很急，用DELPHI判断程序是否运行？没运行则启动它

Answer 1

如何让程序只运行一次？？ 
http://community.csdn.net/Expert/topic/3633/3633504.xml?temp=.1247827

Answer 2

var h:HWND;       
                 Application.Title := 'lch';
                 h:=::FindWindow(0,oldname);//oldename是Application->Title
                 if (h<>nil)then
                 begin
                     ShowMessage("it has run!");
                     Application.Terminate();
                     return 0;
                 end;

Answer 3

var
  mHandle, fHandle: THandle;
begin
  Application.Initialize;
  mHandle := Windows.CreateMutex(nil, true, 'SendMessage');//SendMessage
  if mHandle <> 0 then
  begin
    if GetLastError = ERROR_ALREADY_EXISTS then
    begin
      fHandle := FindWindow(PChar( 'Tfrom1'), nil);
      if (fHandle>0) then
      begin
        ShowMessage("it has run!");
        SetForeGroundWindow(fHandle);
        Windows.ReleaseMutex(mHandle);
      end;
      Halt;
    end;
  end;