C# WINFORM判断程序是否运行，且只能运行一个实例

static class Program
{
private static System.Threading.Mutex mutex;

/// <summary>
/// 应用程序的主入口点。
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);

mutex = new System.Threading.Mutex(true, "OnlyRun");
if (mutex.WaitOne(0, false))
{
Application.Run(new MainForm());
}
else
{
MessageBox.Show("程序已经在运行！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
Application.Exit();
}
}
}

static class Program
{
/// <summary>
/// 应用程序的主入口点。
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);

// get the name of our process
string p = System.Diagnostics.Process.GetCurrentProcess().ProcessName;
// get the list of all processes by that name
System.Diagnostics.Process[] processes = System.Diagnostics.Process.GetProcessesByName(p);
// if there is more than one process
if (processes.Length > 1)
{
MessageBox.Show("程序已经在运行中", "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
Application.Exit();
}
else
{
Application.Run(new MainForm());
}
}
}