关于硬盘序列号的类

using System;
 using System.IO;
 using System.Runtime.InteropServices;
 using System.Text;
 using Microsoft.Win32;namespace Wjb.ReadOrWriteIniAndReg
 {
      /// <summary>
      /// HardDiskVal 的摘要说明。
      /// 读取指定盘符的硬盘序列号
      /// 功能：读取指定盘符的硬盘序列号
      /// </summary>
      public class HardDiskVal
      {
          [DllImport("kernel32.dll")]
          private static extern int GetVolumeInformation(              string  lpRootPathName,
              string  lpVolumeNameBuffer,
              int  nVolumeNameSize,
              ref int  lpVolumeSerialNumber,
              int  lpMaximumComponentLength,
              int  lpFileSystemFlags,
              string  lpFileSystemNameBuffer,
              int  nFileSystemNameSize
              );
         /// <summary>
         /// 获得盘符为drvID的硬盘序列号，缺省为C
         /// </summary>
         /// <param name="drvID"></param>
         /// <returns></returns>
         public string HDVal(string drvID)
         {
              const int MAX_FILENAME_LEN = 256;
              int retVal = 0;
              int a =0;
              int b =0;
              string str1 = null;
              string str2 = null;
              int i = GetVolumeInformation(
                   drvID + @":\",
                   str1,
                   MAX_FILENAME_LEN,
                   ref retVal,
                   a,
                   b,
                   str2,
                   MAX_FILENAME_LEN
                   );
              return retVal.ToString();
         }
         public string HDVal()
         {
              const int MAX_FILENAME_LEN = 256;
              int retVal = 0;
              int a =0;
              int b =0;
              string str1 = null;
              string str2 = null;
              int i = GetVolumeInformation(
                   "c:\\",
                   str1,
                   MAX_FILENAME_LEN,
                   ref retVal,
                   a,
                   b,
                   str2,
                   MAX_FILENAME_LEN
                   );
              return retVal.ToString();
         }
     } 
}