/// <summary>Serializes an <c>XMPMeta</c>-object as RDF into a string.</summary>
/// <remarks>
/// <em>Note:</em> Encoding is forced to UTF-16 when serializing to a
/// string to ensure the correctness of "exact packet size".
/// </remarks>
/// <param name="xmp">a metadata implementation object</param>
/// <param name="options">Options to control the serialization (see <see cref="SerializeOptions"/>).</param>
/// <returns>Returns a string containing the serialized RDF.</returns>
/// <exception cref="XmpException">on serialization errors.</exception>
public static string SerializeToString(XmpMeta xmp, SerializeOptions options)
{
// forces the encoding to be UTF-16 to get the correct string length
options = options ?? new SerializeOptions();
options.EncodeUtf16Be = true;
var output = new MemoryStream(2048);
Serialize(xmp, output, options);
try
{
#if PORTABLE
return options.GetEncoding().GetString(output.ToArray(), 0, (int)output.Length);
#else
return options.GetEncoding().GetString(output.GetBuffer(), 0, (int)output.Length);
#endif
}
catch
{
// Should not happen as UTF-8/16LE/BE are all available
return output.ToString();
}
}
// UTF-8
/// <summary>The actual serialization.</summary>
/// <param name="xmp">the metadata object to be serialized</param>
/// <param name="stream">outputStream the output stream to serialize to</param>
/// <param name="options">the serialization options</param>
/// <exception cref="XmpException">If case of wrong options or any other serialization error.</exception>
public void Serialize(IXmpMeta xmp, Stream stream, SerializeOptions options)
{
try
{
_stream = stream;
_startPos = _stream.Position;
_writer = new StreamWriter(_stream, options.GetEncoding());
_xmp = (XmpMeta)xmp;
_options = options;
_padding = options.Padding;
_writer = new StreamWriter(_stream, options.GetEncoding());
CheckOptionsConsistence();
// serializes the whole packet, but don't write the tail yet
// and flush to make sure that the written bytes are calculated correctly
var tailStr = SerializeAsRdf();
_writer.Flush();
// adds padding
AddPadding(tailStr.Length);
// writes the tail
Write(tailStr);
_writer.Flush();
_stream.Close();
}
catch (IOException)
{
throw new XmpException("Error writing to the OutputStream", XmpErrorCode.Unknown);
}
}
