在c#项目的主入口点加入以下代码:
using System.Diagnostics;
using System.IO;
static void Main()
{
string MName = Process.GetCurrentProcess().MainModule.ModuleName;
string PName = Path.GetFileNameWithoutExtension(MName);
Process[] myProcess = Process.GetProcessesByName(PName);
if (myProcess.Length > 1)
{
MessageBox.Show("系统已经在运行中!", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
else
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new frmLogin());
}
}