C # Read media information

Using system;
Using system. Collections. Generic;
Using system. text;
Using system. IO;
Namespace foxer_player_1. _ 1
{
Public struct mp3info
{
Public String identify; // tag, three bytes
Public String title; // song name, 30 bytes
Public String artist; // artist name, 30 bytes
Public String album; // The album name, 30 bytes.
Public String year; // year, 4 characters long
Public String comment; // comment, 28 bytes
Public char reserved1; // Reserved Bit, one byte
Public char reserved2; // Reserved Bit, one byte
Public char reserved3; // reserved byte
}
/// <Summary>
/// MP3 file information
/// </Summary>
Public class mp3fileinfo
{
Mp3info Info;
/// <Summary>
/// Constructor. Enter the file name to obtain the information.
/// </Summary>
/// <Param name = "mp3filepos"> </param>
Public mp3fileinfo (string mp3filepos)
{
Info = getmp3info (getlast128 (mp3filepos ));
}
/// <Summary>
/// Obtain the sorted MP3 file name. The file name is determined by the title and artist name.
/// </Summary>
/// <Returns> </returns>
Public String getoriginalname ()
{
Return formatstring (info. Title. Trim () + "-" + formatstring (info. Artist. Trim ());
}
/// <Summary>
/// Remove \ 0 characters
/// </Summary>
/// <Param name = "str"> </param>
/// <Returns> </returns>
Private Static string formatstring (string Str)
{
Return Str. Replace ("\ 0 ","");
}
/// <Summary>
/// Obtain the last 128 bytes of the MP3 file
/// </Summary>
/// <Param name = "FILENAME"> file name </param>
/// <Returns> Returns a byte array </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>
/// Obtain information about mp3 songs
/// </Summary>
/// <Param name = "info"> binary information captured from an MP3 file </param>
/// <Returns> Returns a mp3info structure </returns>
Public static mp3info getmp3info (byte [] info)
{
Mp3info mp3info = new mp3info ();
String STR = NULL;
Int I;
Int position = 0; // The starting value of the loop
Int currentindex = 0; // The current index value of info
// Obtain the tag ID
For (I = currentindex; I <currentindex + 3; I ++)
{
STR = STR + (char) info [I];
Position ++;
}
Currentindex = position;
Mp3info. Identify = STR;

// Obtain the song name
STR = NULL;
Byte [] byttitle = new byte [30]; // read the song name to a separate array.
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 );

// Obtain the artist name
STR = NULL;
J = 0;
Byte [] bytartist = new byte [30]; // read the singer's name in a separate array.
For (I = currentindex; I <currentindex + 30; I ++)
{
Bytartist [J] = info [I];
Position ++;
J ++;
}
Currentindex = position;
Mp3info. Artist = foxer_player_1. _ 1. mp3fileinfo. bytetostring (bytartist );

// Obtain the recording name
STR = NULL;
J = 0;
Byte [] bytalbum = new byte [30]; // read the recording name to a separate array.
For (I = currentindex; I <currentindex + 30; I ++)
{
Bytalbum [J] = info [I];
Position ++;
J ++;
}
Currentindex = position;
Mp3info. album = foxer_player_1. _ 1. mp3fileinfo. bytetostring (bytalbum );

// Obtain the year
STR = NULL;
J = 0;
Byte [] bytyear = new byte [4]; // read the year to a separate array.
For (I = currentindex; I <currentindex + 4; I ++)
{
Bytyear [J] = info [I];
Position ++;
J ++;
}
Currentindex = position;
Mp3info. Year = foxer_player_1. _ 1. mp3fileinfo. bytetostring (bytyear );
// Obtain comments
STR = NULL;
J = 0;
Byte [] bytcomment = new byte [28]; // read the comments to a separate array.
For (I = currentindex; I <currentindex + 25; I ++)
{
Bytcomment [J] = info [I];
Position ++;
J ++;
}
Currentindex = position;
Mp3info. Comment = foxer_player_1. _ 1. mp3fileinfo. bytetostring (bytcomment );

// Obtain the reserved bits
Mp3info. reserved1 = (char) info [++ position];
Mp3info. reserved2 = (char) info [++ position];
Mp3info. reserved3 = (char) info [++ position];
Return mp3info;
}
/// <Summary>
/// Convert the byte array into a string
/// </Summary>
/// <Param name = "B"> byte array </param>
/// <Returns> returns the converted string </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); // Remove useless characters
Return STR;
}
}
}