/// <summary>
/// Reads an ID3v2 tag from a stream. Returns null if no ID3v2 tag can be found
/// in the stream.
/// </summary>
/// <param name="stream">The stream to read.</param>
/// <returns>The tag read from the stream, or null if no ID3v2 tag can be found.</returns>
public static ID3v2Tag ReadTag(Stream stream)
{
ID3Versions version = LookForTag(stream);
ID3v2Tag tag = null;
if ((version & ID3Versions.V2) == ID3Versions.V2)
{
tag = new ID3v2Tag();
tag.headerFlags = ReadFlags(stream, version);
int tagSize = ReadTagSize(stream);
// Go to the first byte after the header
stream.Seek(TAG_HEADER_LENGTH, SeekOrigin.Begin);
while (stream.Position < tagSize)
{
ID3v2Frame newFrame = ID3v2Frame.ReadFrame(stream, version);
if (newFrame != null)
{
tag.AddFrame(newFrame);
}
else
{
break;
}
}
}
return(tag);
}
/// <summary>
/// Adds a frame to the tag.
/// </summary>
/// <param name="newFrame">The frame to add.</param>
public void AddFrame(ID3v2Frame newFrame)
{
if (newFrame == null)
{
throw new ArgumentNullException("newFrame");
}
if (frames.ContainsKey(newFrame.Type))
{
ID3v2Frame existingFrame = frames[newFrame.Type];
FrameComposite composite = existingFrame as FrameComposite;
if (composite == null)
{
composite = new FrameComposite(existingFrame.Type);
composite.AddFrame(existingFrame);
frames.Remove(newFrame.Type);
frames.Add(composite.Type, composite);
}
composite.AddFrame(newFrame);
}
else
{
frames.Add(newFrame.Type, newFrame);
}
}
/// <summary>
/// Reads and returns a frame from a stream.
/// </summary>
/// <param name="stream">The stream to read from.</param>
/// <param name="version">The ID3v2 version of the tag being parsed.</param>
/// <returns>The frame read from the stream.</returns>
public static ID3v2Frame ReadFrame(Stream stream, ID3Versions version)
{
if (stream == null)
{
throw new ArgumentNullException("stream");
}
ID3v2Frame frame = null;
FrameParameters parameters = new FrameParameters(version);
byte[] header = new byte[parameters.HeaderLength];
char[] idChars = new char[parameters.IDLength];
byte[] sizeBytes = new byte[parameters.SizeLength];
byte[] flags = new byte[parameters.FlagsLength];
byte[] frameData;
string frameID;
int size;
stream.Read(header, 0, header.Length);
Array.Copy(header, 0, idChars, 0, idChars.Length);
Array.Copy(header, parameters.IDLength, sizeBytes, 0, sizeBytes.Length);
Array.Copy(header, parameters.IDLength + parameters.SizeLength, flags, 0, flags.Length);
if (idChars[0] != 0x0)
{
frameID = new String(idChars);
if (parameters.SizeIsSynchSafe)
{
size = SynchsafeInteger.UnSynchsafe(sizeBytes);
}
else
{
size = EncodedInteger.ToInt(sizeBytes);
}
frameData = new byte[size];
stream.Read(frameData, 0, frameData.Length);
FrameType frameType = FrameRegistry.GetFrameType(frameID, version);
frame = FrameRegistry.GetNewFrame(frameType);
frame.Initialize(flags, frameData, version);
}
else
{
frame = null;
}
return(frame);
}
private ID3v2Frame GetFirstFrame(FrameType frameType)
{
ID3v2Frame frame = null;
if (frames.ContainsKey(frameType))
{
frame = frames[frameType];
FrameComposite composite = frame as FrameComposite;
if (composite != null)
{
frame = composite[0] as ID3v2Frame;
}
}
return(frame);
}
/// <summary>
/// Removes a given frame from the tag.
/// </summary>
/// <param name="frame">The frame to remove.</param>
public void RemoveFrame(ID3v2Frame frame)
{
if (frame == null)
{
throw new ArgumentNullException("frame");
}
if (frames.ContainsKey(frame.Type))
{
ID3v2Frame existingFrame = frames[frame.Type];
FrameComposite composite = existingFrame as FrameComposite;
if (composite != null && composite != frame)
{
composite.RemoveFrame(frame);
}
else
{
frames.Remove(frame.Type);
}
}
}
public virtual ID3v2Frame this[FrameType frameType]
{
get
{
ID3v2Frame frame = null;
if (frames.ContainsKey(frameType))
{
frame = frames[frameType];
}
return(frame);
}
set
{
if (value == null)
{
RemoveFrame(frameType);
}
else
{
AddFrame(value);
}
}
}
/// <summary>
/// Copy constructor.
/// </summary>
/// <param name="frame">Frame to copy.</param>
protected ID3v2Frame(ID3v2Frame frame)
{
this.frameType = frame.frameType;
this.headerFlags = frame.headerFlags;
}
