C#获取mp3 Tag信息

//Foxer_Player_App_Author: CT.ThEN
//Foxer_Player_App_BuildTime: Otc,12,2008
//Foxer_Player_App_Version: 1.01
//Foxer_Player_App_Author_email: ctthen@126.com
//Foxer_Player_mp3Info:get_mp3Info

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
namespace Foxer_Player_1._1
{
public struct Mp3Info
{
public string identify;     //TAG，三个字节
public string Title;        //歌曲名,30个字节
public string Artist;       //歌手名,30个字节
public string Album;        //所属唱片,30个字节
public string Year;         //年,4个字符
public string Comment;      //注释,28个字节
public char reserved1;      //保留位，一个字节
public char reserved2;      //保留位，一个字节
public char reserved3;      //保留位，一个字节
}
/// <summary>
/// Mp3文件信息类
/// </summary>
public class Mp3FileInfo
{
Mp3Info info;
/// <summary>
/// 构造函数,输入文件名即得到信息
/// </summary>
/// <param name="mp3FilePos"></param>
public Mp3FileInfo(String mp3FilePos)
{
info = getMp3Info(getLast128(mp3FilePos));
}
/// <summary>
/// 获取整理后的Mp3文件名,这里以标题和艺术家名定文件名
/// </summary>
/// <returns></returns>
public String GetOriginalName()
{
return formatString(info.Title.Trim()) + "-" + formatString(info.Artist.Trim());
}
/// <summary>
/// 去除/0字符
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
private static String formatString(String str)
{
return str.Replace("/0", "");
}
/// <summary>
/// 获取MP3文件最后128个字节
/// </summary>
/// <param name="FileName">文件名</param>
/// <returns>返回字节数组</returns>
public static byte[] getLast128(string FileName)
{
FileStream fs = new FileStream(FileName, FileMode.Open, FileAccess.Read);
Stream stream = fs;
stream.Seek(-128, SeekOrigin.End);
const int seekPos = 128;
int rl = 0;
byte[] Info = new byte[seekPos];
rl = stream.Read(Info, 0, seekPos);
fs.Close();
stream.Close();
return Info;
}
/// <summary>
/// 获取MP3歌曲的相关信息
/// </summary>
/// <param name = "Info">从MP3文件中截取的二进制信息</param>
/// <returns>返回一个Mp3Info结构</returns>
public static Mp3Info getMp3Info(byte[] Info)
{
Mp3Info mp3Info = new Mp3Info();
string str = null;
int i;
int position = 0;//循环的起始值
int currentIndex = 0;//Info的当前索引值
//获取TAG标识
for (i = currentIndex; i < currentIndex + 3; i++)
{
str = str + (char)Info[i];
position++;
}
currentIndex = position;
mp3Info.identify = str;

//获取歌名
str = null;
byte[] bytTitle = new byte[30];//将歌名部分读到一个单独的数组中
int j = 0;
for (i = currentIndex; i < currentIndex + 30; i++)
{
bytTitle[j] = Info[i];
position++;
j++;
}
currentIndex = position;
mp3Info.Title = Foxer_Player_1._1.Mp3FileInfo.byteToString(bytTitle);

//获取歌手名
str = null;
j = 0;
byte[] bytArtist = new byte[30];//将歌手名部分读到一个单独的数组中
for (i = currentIndex; i < currentIndex + 30; i++)
{
bytArtist[j] = Info[i];
position++;
j++;
}
currentIndex = position;
mp3Info.Artist = Foxer_Player_1._1.Mp3FileInfo.byteToString(bytArtist);

//获取唱片名
str = null;
j = 0;
byte[] bytAlbum = new byte[30];//将唱片名部分读到一个单独的数组中
for (i = currentIndex; i < currentIndex + 30; i++)
{
bytAlbum[j] = Info[i];
position++;
j++;
}
currentIndex = position;
mp3Info.Album = Foxer_Player_1._1.Mp3FileInfo.byteToString(bytAlbum);

//获取年
str = null;
j = 0;
byte[] bytYear = new byte[4];//将年部分读到一个单独的数组中
for (i = currentIndex; i < currentIndex + 4; i++)
{
bytYear[j] = Info[i];
position++;
j++;
}
currentIndex = position;
mp3Info.Year = Foxer_Player_1._1.Mp3FileInfo.byteToString(bytYear);
//获取注释
str = null;
j = 0;
byte[] bytComment = new byte[28];//将注释部分读到一个单独的数组中
for (i = currentIndex; i < currentIndex + 25; i++)
{
bytComment[j] = Info[i];
position++;
j++;
}
currentIndex = position;
mp3Info.Comment = Foxer_Player_1._1.Mp3FileInfo.byteToString(bytComment);

//以下获取保留位
mp3Info.reserved1 = (char)Info[++position];
mp3Info.reserved2 = (char)Info[++position];
mp3Info.reserved3 = (char)Info[++position];
return mp3Info;
}
/// <summary>
/// 将字节数组转换成字符串
/// </summary>
/// <param name = "b">字节数组</param>
/// <returns>返回转换后的字符串</returns>
public static string byteToString(byte[] b)
{
Encoding enc = Encoding.GetEncoding("GB2312");
string str = enc.GetString(b);
str = str.Substring(0, str.IndexOf("#CONTENT#") >= 0 ? str.IndexOf("#CONTENT#") : str.Length);//去掉无用字符
return str;
}
}
}