Process Protection C#

using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
using System.Runtime.InteropServices;
public class clsProcessProtect
{

    [DllImport("ntdll")]
    private static extern int NtSetInformationProcess(IntPtr hProcess, int processInformationClass, ref int processInformation, int processInformationLength);

    EventHandler psStop = new EventHandler(StopProcessProtection);
    const  iStop = 0;
    const  iStart = 1;
    const  ProcessPriorityClass = 29;
    public clsProcessProtect()
    {
    }

    public clsProcessProtect()
    {
    }

    public void Start()
    {
        StartProcessProtection(ref iStart);
        AppDomain.CurrentDomain.ProcessExit += psStop;
        AppDomain.CurrentDomain.DomainUnload += psStop;
        Application.ApplicationExit += psStop;
    }

    private bool StartProcessProtection(ref int psInfo)
    {
        try {
            NtSetInformationProcess(Process.GetCurrentProcess().Handle, ProcessPriorityClass, ref psInfo, Marshal.SizeOf(psInfo));
            return true;
        } catch (Exception ex) {
            MessageBox.Show(ex.Message + Constants.vbNewLine + ex.InnerException.ToString());
        }

    }

    private bool StopProcessProtection()
    {
        try {
            StartProcessProtection(ref iStop);
        } catch (Exception ex) {
            MessageBox.Show(ex.Message + "\n" + ex.InnerException.ToString());
        }
    }

}