在做Delphi的一个小工具的时候,要让自己的程序保证只启动一个实例如下有几种方法实现:
1.使用系统函数FindWindows()函数来实现:
program Project1;
uses
  Forms, Windows,//添加Windows单元
  offertool in 'offertool.pas' {foffertool},
  MyThread in 'MyThread.pas',
  offerchild in 'offerchild.pas' {fofferchild};
{$R *.res}
var
  Hwnd:THandle;  //添加一个句柄
begin
  Hwnd := FindWindow('Tfoffertool',nil);  //参数1:窗口类名,参数2:窗口标题
  if Hwnd=0 then
  begin
    Application.Initialize;
    Application.CreateForm(Tfoffertool, foffertool);
    Application.Run;
  end
  else
  begin
    Application.MessageBox('已经运行了一个实例','提示',MB_OK);
  end;
end.
2.使用使用互斥对象来实现:
program Project1;
uses
  Forms, Windows, //添加Windows单元
  offertool in 'offertool.pas' {foffertool},
  MyThread in 'MyThread.pas',
  offerchild in 'offerchild.pas' {fofferchild};
{$R *.res}
var
  myMutex:THandle; //添加一个互斥锁句柄
begin
  myMutex := CreateMutex(nil,True,'新股代理申购报盘');
  if GetLastError<>ERROR_ALREADY_EXISTS then
  begin
    Application.Initialize;
    Application.CreateForm(Tfoffertool, foffertool);
    Application.Run;
  end
  else
    Application.MessageBox('已经运行了一个实例','提示',MB_OK);
end.

