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();
        }
    }
}