C# Quoted-Printable编码、解码

# using System; 
# using System.Collections; 
# using System.Text; 
# 
# /// <summary> 
# /// Class for encoding and decoding a string to QuotedPrintable 
# /// RFC 1521 http://www.ietf.org/rfc/rfc1521.txt 
# /// RFC 2045 http://www.ietf.org/rfc/rfc2045.txt 
# /// Date: 2006-03-23 
# /// Author: Kevin Spaun 
# /// Company: SPAUN Informationstechnik GmbH - http://www.spaun-it.com/ 
# /// Feedback: kspaun@spaun-it.de 
# /// License: This piece of code comes with no guaranties. You can use it for whatever you want for free. 
# /// 
# /// Modified by Will Huang ( http://blog.miniasp.com/post/2008/02/14/Quoted-Printable-Encoding-and-Decoding.aspx ) 
# /// Modified at 2008-02-13 
# /// 
# /// Modified by reterry (http://www.jb51.net) 
# /// Modified at 2008-11-29 
# /// Modified for MySelf 
# /// 
# /// </summary> 
# public class QuotedPrintable 
# { 
# private const byte EQUALS = 61; 
# private const byte CR = 13; 
# private const byte LF = 10; 
# private const byte SPACE = 32; 
# private const byte TAB = 9; 
# 
# /// <summary> 
# /// Encodes a string to QuotedPrintable 
# /// </summary> 
# /// <param name="_ToEncode">String to encode</param> 
# /// <returns>QuotedPrintable encoded string</returns> 
# public static string Encode(string _ToEncode) 
# { 
# StringBuilder Encoded = new StringBuilder(); 
# string hex = string.Empty; 
# //byte[] bytes = Encoding.Default.GetBytes(_ToEncode); 
# byte[] bytes = Encoding.UTF8.GetBytes(_ToEncode); 
# //int count = 0; 
# 
# for (int i = 0; i < bytes.Length; i++) 
# { 
# //these characters must be encoded 
# if ((bytes[i] < 33 || bytes[i] > 126 || bytes[i] == EQUALS) && bytes[i] != CR && bytes[i] != LF && bytes[i] != SPACE) 
# { 
# if (bytes[i].ToString("X").Length < 2) 
# { 
# hex = "0" + bytes[i].ToString("X"); 
# Encoded.Append("=" + hex); 
# } 
# else 
# { 
# hex = bytes[i].ToString("X"); 
# Encoded.Append("=" + hex); 
# } 
# } 
# else 
# { 
# //check if index out of range 
# if ((i + 1) < bytes.Length) 
# { 
# //if TAB is at the end of the line - encode it! 
# if ((bytes[i] == TAB && bytes[i + 1] == LF) || (bytes[i] == TAB && bytes[i + 1] == CR)) 
# { 
# Encoded.Append("=0" + bytes[i].ToString("X")); 
# } 
# //if SPACE is at the end of the line - encode it! 
# else if ((bytes[i] == SPACE && bytes[i + 1] == LF) || (bytes[i] == SPACE && bytes[i + 1] == CR)) 
# { 
# Encoded.Append("=" + bytes[i].ToString("X")); 
# } 
# else 
# { 
# Encoded.Append(System.Convert.ToChar(bytes[i])); 
# } 
# } 
# else 
# { 
# Encoded.Append(System.Convert.ToChar(bytes[i])); 
# } 
# } 
# //if (count == 75) 
# //{ 
# // Encoded.Append("=\r\n"); //insert soft-linebreak 
# // count = 0; 
# //} 
# //count++; 
# } 
# 
# return Encoded.ToString(); 
# } 
# 
# /// <summary> 
# /// Decodes a QuotedPrintable encoded string 
# /// </summary> 
# /// <param name="_ToDecode">The encoded string to decode</param> 
# /// <returns>Decoded string</returns> 
# public static string Decode(string _ToDecode) 
# { 
# //remove soft-linebreaks first 
# //_ToDecode = _ToDecode.Replace("=\r\n", ""); 
# 
# char[] chars = _ToDecode.ToCharArray(); 
# 
# byte[] bytes = new byte[chars.Length]; 
# 
# int bytesCount = 0; 
# 
# for (int i = 0; i < chars.Length; i++) 
# { 
# // if encoded character found decode it 
# if (chars[i] == '=') 
# { 
# bytes[bytesCount++] = System.Convert.ToByte(int.Parse(chars[i + 1].ToString() + chars[i + 2].ToString(), System.Globalization.NumberStyles.HexNumber)); 
# 
# i += 2; 
# } 
# else 
# { 
# bytes[bytesCount++] = System.Convert.ToByte(chars[i]); 
# } 
# } 
# 
# //return System.Text.Encoding.Default.GetString(bytes, 0, bytesCount); 
# return System.Text.Encoding.UTF8.GetString(bytes, 0, bytesCount); 
# } 
# }