C#(csharp) Code to Reads/writes mp3 Id3v1 tags.

Reads/writes mp3 Id3v1 tags

SOURCE CODE:
using System;
using System.IO;
using System.Text;

namespace mp3info
{

public class ID3v1
{
public string filename;

public string Title;
public string Artist;
public string Album;
public string Year;
public string Comment;
public int GenreID;
public int Track;

public bool hasTag;

private void Initialize_Components()
{
hasTag = false;
filename = "";
Title = "";
Artist = "";
Album = "";
Year = "";
Comment = "";

GenreID = 0;
Track = 0;
}


public ID3v1()
{
Initialize_Components();
}

public ID3v1( string filename )
{
Initialize_Components();
this.filename = filename;
}


public void Read ()
{
// Read the 128 byte ID3 tag into a byte array
FileStream? oFileStream;
oFileStream = new FileStream( this.filename, FileMode?.Open);
byte[] bBuffer = new byte128;
oFileStream.Seek(-128, SeekOrigin?.End);
oFileStream.Read(bBuffer,0, 128);
oFileStream.Close();

// Convert the Byte Array to a String
Encoding instEncoding = new ASCIIEncoding(); // NB: Encoding is an Abstract class
string id3Tag = instEncoding.GetString(bBuffer);

// If there is an attched ID3 v1.x TAG then read it
if (id3Tag .Substring(0,3) == "TAG")
{
this.Title = id3Tag.Substring( 3, 30).Trim();
this.Artist = id3Tag.Substring( 33, 30).Trim();
this.Album = id3Tag.Substring( 63, 30).Trim();
this.Year = id3Tag.Substring( 93, 4).Trim();
this.Comment = id3Tag.Substring( 97,28).Trim();

// Get the track number if TAG conforms to ID3 v1.1
if (id3Tag125==0)
this.Track = bBuffer126;
else
this.Track = 0;
this.GenreID = bBuffer127;

this.hasTag = true;
// ********* IF USED IN ANGER: ENSURE to test for non-numeric year
}
else
{
this.hasTag = false;
}
}

public void updateMP3Tag ()
{
// Trim any whitespace
this.Title = this.Title.Trim();
this.Artist = this.Artist.Trim();
this.Album = this.Album.Trim();
this.Year = this.Year.Trim();
this.Comment = this.Comment.Trim();

// Ensure all properties are correct size
if (this.Title.Length > 30) this.Title = this.Title.Substring(0,30);
if (this.Artist.Length > 30) this.Artist = this.Artist.Substring(0,30);
if (this.Album.Length > 30) this.Album = this.Album.Substring(0,30);
if (this.Year.Length > 4) this.Year = this.Year.Substring(0,4);
if (this.Comment.Length > 28) this.Comment = this.Comment.Substring(0,28);

// Build a new ID3 Tag (128 Bytes)
byte[] tagByteArray = new byte128;
for ( int i = 0; i < tagByteArray.Length; i++ ) tagByteArrayi = 0; // Initialise array to nulls

// Convert the Byte Array to a String
Encoding instEncoding = new ASCIIEncoding(); // NB: Encoding is an Abstract class // ************ To DO: Make a shared instance of ASCIIEncoding so we don't keep creating/destroying it
// Copy "TAG" to Array
byte[] workingByteArray = instEncoding.GetBytes("TAG");
Array.Copy(workingByteArray, 0, tagByteArray, 0, workingByteArray.Length);
// Copy Title to Array
workingByteArray = instEncoding.GetBytes(this.Title);
Array.Copy(workingByteArray, 0, tagByteArray, 3, workingByteArray.Length);
// Copy Artist to Array
workingByteArray = instEncoding.GetBytes(this.Artist);
Array.Copy(workingByteArray, 0, tagByteArray, 33, workingByteArray.Length);
// Copy Album to Array
workingByteArray = instEncoding.GetBytes(this.Album);
Array.Copy(workingByteArray, 0, tagByteArray, 63, workingByteArray.Length);
// Copy Year to Array
workingByteArray = instEncoding.GetBytes(this.Year);
Array.Copy(workingByteArray, 0, tagByteArray, 93, workingByteArray.Length);
// Copy Comment to Array
workingByteArray = instEncoding.GetBytes(this.Comment);
Array.Copy(workingByteArray, 0, tagByteArray, 97, workingByteArray.Length);
// Copy Track and Genre to Array
tagByteArray126 = System.Convert.ToByte(this.Track);
tagByteArray127 = System.Convert.ToByte(this.GenreID);

// SAVE TO DISK: Replace the final 128 Bytes with our new ID3 tag
FileStream? oFileStream = new FileStream(this.filename , FileMode?.Open);
if (this.hasTag)
oFileStream.Seek(-128, SeekOrigin?.End);
else
oFileStream.Seek(0, SeekOrigin?.End);
oFileStream.Write(tagByteArray,0, 128);
oFileStream.Close();
this.hasTag = true;
}

}
}