/// <summary>
/// Decode rfc 2047 definition of quoted-printable
/// </summary>
/// <param name="charset">charset to use when decoding</param>
/// <param name="orig"><c>string</c> to decode</param>
/// <returns>the decoded <see cref="System.String" /></returns>
public static System.String QuotedPrintable2Unicode(System.String charset, System.String orig)
{
System.Text.Encoding enc = MimeTools.parseCharSet(charset);
if (enc == null || orig == null)
{
return(orig);
}
MimeTools.QuotedPrintable2Unicode(enc, ref orig);
return(orig);
}
/// <summary>
/// rfc 2047 header body decoding
/// </summary>
/// <param name="word"><c>string</c> to decode</param>
/// <returns>the decoded <see cref="System.String" /></returns>
public static System.String rfc2047decode(System.String word)
{
System.String[] words;
System.String[] wordetails;
System.Text.RegularExpressions.Regex rfc2047format = new System.Text.RegularExpressions.Regex(@"(=\?[\-a-zA-Z0-9]+\?[qQbB]\?[a-zA-Z0-9=_\-\.$%&/\'\\!:;{}\+\*\|@#~`^]+\?=)\s*", System.Text.RegularExpressions.RegexOptions.ECMAScript);
// No rfc2047 format
if (!rfc2047format.IsMatch(word))
{
#if LOG
if (log.IsDebugEnabled)
{
log.Debug("Not a RFC 2047 string: " + word);
}
#endif
return(word);
}
#if LOG
if (log.IsDebugEnabled)
{
log.Debug("Decoding 2047 string: " + word);
}
#endif
words = rfc2047format.Split(word);
word = System.String.Empty;
rfc2047format = new System.Text.RegularExpressions.Regex(@"=\?([\-a-zA-Z0-9]+)\?([qQbB])\?([a-zA-Z0-9=_\-\.$%&/\'\\!:;{}\+\*\|@#~`^]+)\?=", System.Text.RegularExpressions.RegexOptions.ECMAScript);
for (int i = 0; i < words.GetLength(0); i++)
{
if (!rfc2047format.IsMatch(words[i]))
{
word += words[i];
continue;
}
wordetails = rfc2047format.Split(words[i]);
switch (wordetails[2])
{
case "q":
case "Q":
word += MimeTools.QuotedPrintable2Unicode(wordetails[1], wordetails[3]).Replace('_', ' ');;
break;
case "b":
case "B":
try {
System.Text.Encoding enc = System.Text.Encoding.GetEncoding(wordetails[1]);
System.Byte[] ch = System.Convert.FromBase64String(wordetails[3]);
word += enc.GetString(ch);
} catch (System.Exception) {
}
break;
}
}
#if LOG
if (log.IsDebugEnabled)
{
log.Debug("Decoded 2047 string: " + word);
}
#endif
return(word);
}