C#判断当前启动程序进程是否存在

System.Threading.Mutex mutex;//注意，此变量要定义为成员变量，而不是局部变量

bool CheckMultiInstance()
{
bool createdNew = true;

mutex = new System.Threading.Mutex(true, "_TEST_Mutex_", out createdNew);//这种在系统多用户下，每个用户能启动一个程序进程。

mutex = new System.Threading.Mutex(true, "Global\\_TEST_Mutex_", out createdNew);//这种在系统中，不管几个用户，只能存在一个这样的程序进程

if (!createdNew)
{
MessageBox.Show("Program is already running.");
}
return createdNew;
}

/// <summary>
/// Is exist same process
/// </summary>
/// <returns></returns>
public static Process GetExistProcess()
{
try
{
var current = Process.GetCurrentProcess();
var pArrayy = System.Diagnostics.Process.GetProcessesByName(current.ProcessName);

if (pArrayy == null || pArrayy.Length == 0)
{
return null;
}
foreach (var item in pArrayy)
{
try
{

if (!item.ProcessName.ToUpper().Contains(current.ProcessNameToUpper()))
{
continue;
}
if (item.Id != current.Id && item.MainModule.ModuleName.ToUpper() == current.MainModule.ModuleName.ToUpper())
{
return item;
}
}
catch (Exception er)
{
LogHelper.WriteException(er);
continue;
}

}
}
catch (Exception ex)
{
LogHelper.WriteException(ex);
}
return null;

}