C# WinForm 判断程序是否已经在运行，且只允许运行一个实例
staticclassProgram
{
/// <summary>
/// 应用程序的主入口点。
/// </summary>
[STAThread]
staticvoidMain()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
//1.这里判定是否已经有实例在运行
//只运行一个实例
Process instance = RunningInstance();
if(instance ==null)
{
//1.1 没有实例在运行
Application.Run(newfrmMain());
}
else
{
//1.2 已经有一个实例在运行
HandleRunningInstance(instance);
}
//Application.Run(new frmMain());
}
//2.在进程中查找是否已经有实例在运行
#region 确保程序只运行一个实例
privatestaticProcess 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 processinprocesses)
{
//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
returnprocess;
}
}
}
returnnull;
}
//3.已经有了就把它激活，并将其窗口放置最前端
privatestaticvoidHandleRunningInstance(Process instance)
{
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")]
privatestaticexternboolShowWindowAsync(System.IntPtr hWnd,intcmdShow);
[DllImport("User32.dll")]
privatestaticexternboolSetForegroundWindow(System.IntPtr hWnd);
#endregion
}
转载 http://www.jb51.net/article/82124.htm