C#判断当前系统是32位还是64位

// The initial C# code for the "plain" WMI query was generated by WMI Code Generator, Version 5.00, http://www.robvanderwoude.com/wmigen.php

using System;
using System.Management;
using System.Collections.Generic;

namespace Win32_Processor_Query
{
    public class WMIQuery
    {
        public static int Main(string[] args)
        {
            string fullpath = Environment.GetCommandLineArgs().GetValue(0).ToString();
            string[] program = fullpath.Split('\\');
            string exename = program[program.GetUpperBound(0)];
            exename = exename.Substring(0, exename.IndexOf('.'));

            if (args.Length > 0)
            {
                Console.OpenStandardError();
                Console.WriteLine();
                Console.WriteLine(exename + ",  Version 1.00");
                Console.WriteLine("Detect if running in a 32-bit or 64-bit OS");
                Console.WriteLine();
                Console.WriteLine("Usage:  " + exename.ToUpper() + "  [ computername ]");
                Console.WriteLine();
                Console.WriteLine("Where:  \"computername\"  is the (optional) name of a remote computer");
                Console.WriteLine("                        (default if not specified: local computer)");
                Console.WriteLine();
                Console.WriteLine("Note:   Return value (\"ErrorLevel\") 32 or 64 equals OS value");
                Console.WriteLine();
                Console.WriteLine("Written by Rob van der Woude");
                Console.WriteLine("http://www.robvanderwoude.com");
                Console.OpenStandardOutput();
                return 1;
            }
            try
            {
                string wmins = "root\\CIMV2";
                if (args.Length == 1)
                {
                    wmins = "\\\\" + args[0] + "\\" + wmins;

                }

                UInt16 addresswidth = 0;

                ManagementObjectSearcher searcher = new ManagementObjectSearcher(wmins, "SELECT * FROM Win32_Processor");

                foreach (ManagementObject queryObj in searcher.Get())
                {
                    addresswidth = (UInt16) (queryObj["AddressWidth"]);
                    Console.WriteLine("Windows   : {0}-bit", addresswidth);
                    Console.WriteLine("Processor : {0}-bit", queryObj["DataWidth"]);
                }

                return addresswidth;
            }
            catch (Exception e)
            {
                Console.OpenStandardError();
                Console.WriteLine("Error: " + e.Message);
                Console.WriteLine();
                Console.WriteLine("For detailed help, run: " + exename + " /?");
                Console.OpenStandardOutput();
                return 1;
            }
        }
    }
}