public static string DecodeMIME(string mimeString, e_Encoding_Type e_Type, string Charset)
{
// Example: mimeString = "=?Windows-1252?Q?Registered_Member_News=3A_WPC09_to_feature_Windows_7=2C_?==?Windows-1252?Q?_Office=2C_Exchange=2C_more=85?="
// In this example two Q-encoded strings are defined!
string encodedString = mimeString;
string decodedString = "";
while (encodedString.Length > 0)
{
Match match = Regex.Match(encodedString, @"=\?(?<charset>.*?)\?(?<encoding>[qQbB])\?(?<value>.*?)\?=");
if (match.Success)
{
string CurrCharset = match.Groups["charset"].Value;
if (string.IsNullOrEmpty(CurrCharset))
{
CurrCharset = Charset;
}
string value = match.Groups["value"].Value;
e_Encoding_Type e_TypeCurrent = GetEncoding(match.Groups["encoding"].Value.ToLower(), false);
if (e_TypeCurrent == e_Encoding_Type.t_unknown)
{
e_TypeCurrent = e_Type;
}
decodedString += Decode(value, e_TypeCurrent, CurrCharset);
// When multiple entries, subtract the currently decoded part
encodedString = encodedString.Substring(match.Index + match.Length);
}
else
{
// Unable to decode (not mime encoded)
if (!string.IsNullOrEmpty(decodedString))
{
return(decodedString + encodedString);
}
else
{
return(mimeString);
}
}
}
// Successfull
return(decodedString);
}
public static string DecodeEncoding(string Source, e_Encoding_Type this_Encoding)
{
string res = "";
switch (this_Encoding)
{
case e_Encoding_Type.t_base64:
try
{
// not all strings can be decoded
// for example W05vcnRvbiBBbnRpU3BhbV0gS3JlbWxpbi5ydTog0JXQttC10LTQvdC10LLQvdCw0Y8g0YDQsNGB0YHRi9C70LrQsA
// inpossible, but C++ working with it well ???
byte[] Tempval = Convert.FromBase64String(Source);
for (int i = 0; i < Tempval.Length; i++)
{
res += (char)Tempval[i];
}
}
catch
{
res = c_base64.decode(Source);
}
break;
case e_Encoding_Type.t_quoted_printable:
// not realized
//parse looking for =XX where XX is hexadecimal
Regex re = new Regex(
"(\\=([0-9A-F][0-9A-F]))",
RegexOptions.IgnoreCase
);
res = re.Replace(Source, new MatchEvaluator(HexDecoderEvaluator));
res = res.Replace('_', ' ');
break;
case e_Encoding_Type.t_7bit:
case e_Encoding_Type.t_8bit:
case e_Encoding_Type.t_binary:
default:
return(Source);
}
return(res);
}
public static string DecodeMIME(string mimeString, e_Encoding_Type e_Type)
{
return(DecodeMIME(mimeString, e_Type, ""));
}
public static string Decode(byte [] Source, e_Encoding_Type this_Encoding, string ThisCharset)
{
return(DecodeCodePage(DecodeEncoding(Source, this_Encoding), ThisCharset));
}
