How to convert Quoted-Print String

Question

I\'m working on French String in .NET Decoding a Mail body , I receive \"Chasn=C3=A9 sur illet\" I would like to get \"Chasné sur illet\" and i don\'t find any solution ave

Answer 1

We had an issue with this method - that it is VERY slow. The following enhanced performance A LOT

public static string FromMailTransferEncoding(this string messageText, Encoding enc, string transferEncoding)
{
    if (string.IsNullOrEmpty(transferEncoding)) 
        return messageText;

    if ("quoted-printable".Equals(transferEncoding.ToLower())) 
    {
        StringBuilder sb = new StringBuilder();               
        string delimitorRegEx = @"=[\r][\n]";
        string[] parts = Regex.Split(messageText, delimitorRegEx);

        foreach (string part in parts)
        {
            string subPart = part;
            Regex occurences = new Regex(@"(=[0-9A-Z][0-9A-Z])+", RegexOptions.Multiline);
            MatchCollection matches = occurences.Matches(subPart);

            foreach (Match m in matches)
            {
                byte[] bytes = new byte[m.Value.Length / 3];
                for (int i = 0; i < bytes.Length; i++)
                {
                    string hex = m.Value.Substring(i * 3 + 1, 2);
                    int iHex = Convert.ToInt32(hex, 16);
                    bytes[i] = Convert.ToByte(iHex);
                }

                subPart = occurences.Replace(subPart, enc.GetString(bytes), 1);
            }

            sb.Append(subPart);
        }
        return sb.ToString();
    }        
return messageText;
}