CSHARP

shutdown system C#

Process.Start("shutdown","/s /t 0");

shutdown system C#

var psi = new ProcessStartInfo("shutdown","/s /t 0");
psi.CreateNoWindow = true;
psi.UseShellExecute = false;
Process.Start(psi);
// to avoid creating window

shutdown system C#

using System.Management;

void Shutdown()
{
    ManagementBaseObject mboShutdown = null;
    ManagementClass mcWin32 = new ManagementClass("Win32_OperatingSystem");
    mcWin32.Get();

    // You can't shutdown without security privileges
    mcWin32.Scope.Options.EnablePrivileges = true;
    ManagementBaseObject mboShutdownParams =
             mcWin32.GetMethodParameters("Win32Shutdown");

     // Flag 1 means we want to shut down the system. Use "2" to reboot.
    mboShutdownParams["Flags"] = "1";
    mboShutdownParams["Reserved"] = "0";
    foreach (ManagementObject manObj in mcWin32.GetInstances())
    {
        mboShutdown = manObj.InvokeMethod("Win32Shutdown", 
                                       mboShutdownParams, null);
    }
}