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 byte[128];
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 (id3Tag[125]==0)
this.Track = bBuffer[126];
else
this.Track = 0;
this.GenreID = bBuffer[127];
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 byte[128];
for ( int i = 0; i < tagByteArray.Length; i++ ) tagByteArray[i] = 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
tagByteArray[126] = System.Convert.ToByte(this.Track);
tagByteArray[127] = 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;
}
}
}Introduction
This article shows, how one omitted the detail information of a file under the use of the Shell32.dll from the Windows system. Some detailed information are: Comment, Title, Subject, Category, Author, and so on.
Background
The Windows system could store additional information like author, comment, title, category... to a file, this information can be read with GetDetailsOf method from the shell32.dll.
Using the code
First of all, add a new COM reference "Microsoft Shell Controls and Automation" (shell32.dll) to your Project.
After adding the reference, simple create an instance of the CFileInfo class as in the demo project. To access the File Information, simply read the properties from the class.
try{
// Read File Details from CFileInfo Object
CFileInfo oDetailedFileInfo = new CFileInfo(sFileName);
txtName.Text = oDetailedFileInfo.FileName;
txtFiletype.Text = oDetailedFileInfo.FileType;
txtFileSize.Text = oDetailedFileInfo.FileSize.ToString();
txtAuthor.Text = oDetailedFileInfo.FileAuthor;
txtCategory.Text = oDetailedFileInfo.FileCategory;
txtComment.Text = oDetailedFileInfo.FileComment;
txtSubject.Text = oDetailedFileInfo.FileSubject;
txtTitle.Text = oDetailedFileInfo.FileTitle;
}catch(Exception ex){
MessageBox.Show("Could not read File information\r\n"
+ ex.Message, "Error while getting Info",
MessageBoxButtons.OK,MessageBoxIcon.Error);
}
Behind the Scenes
The GetDetailedFileInfo method gets all available information of a file into an ArrayList. The DetailedFileInfo class is a helper class for holding the information in a simple object within the ArrayList.
// Getting all the available Information of a File into a Arraylist
private ArrayList GetDetailedFileInfo(string sFile){
ArrayList aReturn = new ArrayList();
if(sFile.Length>0){
try{
// Creating a ShellClass Object from the Shell32
ShellClass sh = new ShellClass();
// Creating a Folder Object from Folder that inculdes the File
Folder dir = sh.NameSpace( Path.GetDirectoryName( sFile ) );
// Creating a new FolderItem from Folder that includes the File
FolderItem item = dir.ParseName( Path.GetFileName( sFile ) );
// loop throw the Folder Items
for( int i = 0; i < 30; i++ ) {
// read the current detail Info from the FolderItem Object
//(Retrieves details about an item in a folder.
//For example, its size, type, or the time
//of its last modification.)
// some examples:
// 0 Retrieves the name of the item.
// 1 Retrieves the size of the item.
// 2 Retrieves the type of the item.
// 3 Retrieves the date and time that the item was last modified.
// 4 Retrieves the attributes of the item.
// -1 Retrieves the info tip information for the item.
string det = dir.GetDetailsOf( item, i );
// Create a helper Object for holding the current Information
// an put it into a ArrayList
DetailedFileInfo oFileInfo = new DetailedFileInfo(i,det);
aReturn.Add(oFileInfo);
}
}catch(Exception){
}
}
return aReturn;
}
...
// Helper Class from holding the detailed File Informations
// of the System
public class DetailedFileInfo{
int iID = 0;
string sValue ="";
public int ID{
get{return iID;}
set{iID=value;}
}
public string Value{
get{return sValue;}
set{sValue = value;}
}
public DetailedFileInfo(int ID, string Value){
iID = ID;
sValue = Value;
}
}