internal static string DecodeHeaderValue(string value)
{
int num;
if ((value == null) || (value.Length == 0))
{
return(string.Empty);
}
string[] strArray = value.Split(new char[] { '?' });
if (((strArray.Length != 5) || (strArray[0] != "=")) || (strArray[4] != "="))
{
return(value);
}
string name = strArray[1];
bool flag = strArray[2] == "B";
byte[] bytes = Encoding.ASCII.GetBytes(strArray[3]);
if (flag)
{
num = new Base64Stream().DecodeBytes(bytes, 0, bytes.Length);
}
else
{
num = new QuotedPrintableStream().DecodeBytes(bytes, 0, bytes.Length);
}
return(Encoding.GetEncoding(name).GetString(bytes, 0, num));
}
internal static string EncodeHeaderValue(string value, Encoding encoding, bool base64Encoding)
{
StringBuilder builder = new StringBuilder();
if ((encoding == null) && IsAscii(value, false))
{
return(value);
}
if (encoding == null)
{
encoding = Encoding.GetEncoding("utf-8");
}
string bodyName = encoding.BodyName();
if (encoding == Encoding.BigEndianUnicode)
{
bodyName = "utf-16be";
}
builder.Append("=?");
builder.Append(bodyName);
builder.Append("?");
builder.Append(base64Encoding ? "B" : "Q");
builder.Append("?");
byte[] bytes = encoding.GetBytes(value);
if (base64Encoding)
{
Base64Stream stream = new Base64Stream(-1);
stream.EncodeBytes(bytes, 0, bytes.Length, true);
builder.Append(Encoding.ASCII.GetString(stream.WriteState.Buffer, 0, stream.WriteState.Length));
}
else
{
QuotedPrintableStream stream2 = new QuotedPrintableStream(-1);
stream2.EncodeBytes(bytes, 0, bytes.Length);
builder.Append(Encoding.ASCII.GetString(stream2.WriteState.Buffer, 0, stream2.WriteState.Length));
}
builder.Append("?=");
return(builder.ToString());
}