C# winform设置只能运行一个实例

//=====判断进程法：(修改程序名字后依然能执行)=====
Process current = Process.GetCurrentProcess();
Process[] processes = Process.GetProcessesByName(current.ProcessName);
foreach (Process process in processes)
{
    if (process.Id != current.Id)
    {
        if (process.MainModule.FileName
        == current.MainModule.FileName)
        {
            MessageBox.Show("程序已经运行！", Application.ProductName,
            MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
            return;
        }
    }
}