求：C#下怎样获得机器的CPUID，最好是可以在WEB访问方式下，系统需要验证该机器是否注册。

using System;
using System.Text;
using System.Runtime.InteropServices;
using System.Management;namespace MachineInfo
{
    public class GetInfo
    {
        
        /// <summary>
        /// return Volume Serial Number from hard drive
        /// </summary>
        /// <param name="strDriveLetter">[optional] Drive letter</param>
        /// <returns>[string] VolumeSerialNumber</returns>
        public string GetVolumeSerial(string strDriveLetter)
        {
        if( strDriveLetter=="" || strDriveLetter==null) strDriveLetter="C";
        ManagementObject disk = 
            new ManagementObject("win32_logicaldisk.deviceid=\"" + strDriveLetter +":\"");
        disk.Get();
        return disk["VolumeSerialNumber"].ToString();
        }
        
        /// <summary>
        /// Returns MAC Address from first Network Card in Computer
        /// </summary>
        /// <returns>[string] MAC Address</returns>
        public string GetMACAddress()
            {
            ManagementClass mc = new ManagementClass("Win32_NetworkAdapterConfiguration");
            ManagementObjectCollection moc = mc.GetInstances();
            string MACAddress=String.Empty;
            foreach(ManagementObject mo in moc)
            {
                if(MACAddress==String.Empty)  // only return MAC Address from first card
                {
                    if((bool)mo["IPEnabled"] == true) MACAddress= mo["MacAddress"].ToString() ;
                }
                        mo.Dispose();
            }
            MACAddress=MACAddress.Replace(":","");
            return MACAddress;
            }
        /// <summary>
        /// Return processorId from first CPU in machine
        /// </summary>
        /// <returns>[string] ProcessorId</returns>
        public string GetCPUId()
        {
            string cpuInfo =  String.Empty;
            string temp=String.Empty;
            ManagementClass mc = new ManagementClass("Win32_Processor");
            ManagementObjectCollection moc = mc.GetInstances();
            foreach(ManagementObject mo in moc)
            {
                if(cpuInfo==String.Empty) 
                {// only return cpuInfo from first CPU
                    cpuInfo = mo.Properties["ProcessorId"].Value.ToString();
                }             
            }
            return cpuInfo;
        }
    }
}