/// <summary>
/// Decode the content into the given charset
/// </summary>
private static string DecodeQuotedPrintable(MimeEntity entity)
{
byte[] decodedBytes = QuotedPrintableEncoding.Decode(entity.ContentLines);
if (entity.ContentType.CharSet != null)
{
return(DecodeBytesWithSpecificCharset(decodedBytes, entity.ContentType.CharSet));
}
else
{
// by default, a text/plain ContentType without Specific Charset must default to ISO-8859-1.
// Other text/* ContentType without Specific charset must default to utf-8
// See http://tools.ietf.org/html/rfc6657#page-3
string encodingName = "utf-8";
if (entity.ContentType != null && string.Compare(entity.ContentType.MediaType, "text/plain", true) == 0)
{
encodingName = "ISO-8859-1";
}
string decodedBytesString = Encoding.GetEncoding(encodingName).GetString(decodedBytes);
return(decodedBytesString);
}
}
/// <summary>
/// Sets the decoded content stream by decoding the EncodedMessage
/// and writing it to the entity content stream.
/// </summary>
public static byte[] DecodeBytes(MimeEntity entity)
{
switch (entity.ContentTransferEncoding)
{
case TransferEncoding.Base64:
byte[] decodedBytes = Convert.FromBase64String(Encoding.ASCII.GetString(entity.ContentBytes));
return(decodedBytes);
case TransferEncoding.QuotedPrintable:
return(QuotedPrintableEncoding.Decode(entity.ContentLines));
case TransferEncoding.SevenBit:
default:
return(entity.ContentBytes);
}
}
/// <summary>
/// Decode the received single line using the correct decoder
/// </summary>
internal static string DecodeSingleLineString(string line, TransferEncoding encoding, string charSet)
{
switch (encoding)
{
case TransferEncoding.Base64:
{
byte[] decodedBytes = Encoding.ASCII.GetBytes(line);
return(DecodeBase64(new byte[][] { decodedBytes }, charSet));
}
case TransferEncoding.QuotedPrintable:
{
byte[] decodedBytes = QuotedPrintableEncoding.DecodeSingleLine(line);
return(DecodeBytesWithSpecificCharset(decodedBytes, charSet));
}
case TransferEncoding.SevenBit:
default:
return(line);
}
}
