// 编码private string IMAPEncode(string folder){string rtn = "", base64;int index = 0;   Regex regAsis = new Regex(@"\G(?:[\x20-\x25\x27-\x7e])+");   Regex reg26 = new Regex(@"\G&");   Regex regEncode = new Regex(@"\G(?:[^\x20-\x7e])+");   Regex regEq = new Regex(@"=+$");   Regex regSlash = new Regex(@"\/");while (index < folder.Length) {      Match m;      m = regAsis.Match(folder, index);if(m.Success)      {         index = index + m.Length;         rtn = rtn + m.Value;continue;      }      m = reg26.Match(folder, index);if(m.Success)      {         index = index + m.Length;         rtn = rtn + "&-";continue;      }      m = regEncode.Match(folder, index);if(m.Success)      {         index = index + m.Length;         base64 = Convert.ToBase64String(Encoding.GetEncoding("UTF-16BE").GetBytes(m.Value));         base64 = regEq.Replace(base64, "");         base64 = regSlash.Replace(base64, ",");         rtn = rtn + "&" + base64 + "-";continue;      }   }return rtn;}

// 解码private string IMAPDeconde(string folder){string rtn = "", base64;int index = 0;   Regex regAsis = new Regex(@"\G([^&]+)");   Regex reg26 = new Regex(@"\G\&-");   Regex regDecode = new Regex(@"\G\&([A-Za-z0-9+,]+)-?");   Regex regComma = new Regex(@",");while (index < folder.Length) {      Match m;      m = regAsis.Match(folder, index);if(m.Success)      {         index = index + m.Length;         rtn = rtn + m.Value;continue;      }      m = reg26.Match(folder, index);if(m.Success)      {         index = index + m.Length;         rtn = rtn + "&";continue;      }      m = regDecode.Match(folder, index);if(m.Success)      {         index = index + m.Length;         base64 = m.Value.Substring(1, m.Value.Length - 2);         base64 = regComma.Replace(base64, "/");int mod = base64.Length % 4;if(mod > 0 ) base64 = base64.PadRight(base64.Length + (4 - mod), '=');         base64 = Encoding.GetEncoding("UTF-16BE").GetString(Convert.FromBase64String(base64));         rtn = rtn + base64;continue;      }   }return rtn;}

// 编码public class ImapFolderEncoder {public static String encode(String folder) {    String rtn = "", base64;int index = 0;    Pattern regAsis = Pattern.compile("\\G(?:[\\x20-\\x25\\x27-\\x7e])+");    Pattern reg26 = Pattern.compile("\\G&");    Pattern regEncode = Pattern.compile("\\G(?:[^\\x20-\\x7e])+");    Pattern regEq = Pattern.compile("=+$");    Pattern regSlash = Pattern.compile("\\/");while (index < folder.length()) {        Matcher m;        m = regAsis.matcher(folder);if (m.find(index)) {        index = index + (m.end() - m.start());        rtn = rtn + m.group();continue;        }        m = reg26.matcher(folder);if (m.find(index)) {        index = index + (m.end() - m.start());        rtn = rtn + "&-";continue;        }        m = regEncode.matcher(folder);if (m.find(index)) {        index = index + (m.end() - m.start());        base64 = SimpleUtil.encodeBase64Content(m.group(), "UTF-16BE");        base64 = base64.replaceAll(regEq.pattern(), "");        base64 = base64.replaceAll(regSlash.pattern(), ",");        rtn = rtn + "&" + base64 + "-";continue;        }    }return rtn;    }

}

// 解码public class ImapFolderDecoder {public static String decode(String folder) {    String rtn = "", base64;int index = 0;    Pattern regAsis = Pattern.compile("\\G([^&]+)");    Pattern reg26 = Pattern.compile("\\G\\&-");    Pattern regDecode = Pattern.compile("\\G\\&([A-Za-z0-9+,]+)-?");    Pattern regComma = Pattern.compile(",");while (index < folder.length()) {        Matcher m;        m = regAsis.matcher(folder);if (m.find(index)) {        index = index + (m.end() - m.start());        rtn = rtn + m.group();continue;        }        m = reg26.matcher(folder);if (m.find(index)) {        index = index + (m.end() - m.start());        rtn = rtn + "&";continue;        }        m = regDecode.matcher(folder);if (m.find(index)) {        index = index + (m.end() - m.start());        base64 = m.group().substring(1, m.group().length() - 1);        base64 = base64.replaceAll(regComma.pattern(), "/");int mod = base64.length() % 4;int count = 4 - mod;while (count > 0) {            base64 += "=";            count--;        }        base64 = SimpleUtil.base64Decode(base64, "UTF-16BE");        rtn = rtn + base64;continue;        }    }return rtn;    }}

// 编码function IMAPEncode($sStr){$sOut = '';$sBase64 = '';$nIndex = 0;$sRegAsis = '/^(?:[\x20-\x25\x27-\x7e])+/';$sReg26 = '/^&/';$sRegEncode = '/^(?:[^\x20-\x7e])+/';$sRegEq = '/=+$/';$sRegSlash = '/\//';

while ($nIndex < strlen($sStr))    {$aTmp = array();$nResult = preg_match($sRegAsis, $sStr, &$aTmp, null, $nIndex);if ($nResult)        {$nIndex += strlen($aTmp[0]);$sOut .= $aTmp[0];continue;        }$nResult = preg_match($sReg26, $sStr, &$aTmp, null, $nIndex);if ($nResult)        {$nIndex += strlen($aTmp[0]);$sOut .= '&-';continue;        }$nResult = preg_match($sRegEncode, $sStr, &$aTmp, null, $nIndex);if ($nResult)        {$nIndex += strlen($aTmp[0]);$sBase64 = base64_encode(iconv('UTF-8', 'UTF-16BE', $aTmp[0]));$sBase64 = preg_replace($sRegEq, '', $sBase64);$sBase64 = preg_replace($sRegSlash, ',', $sBase64);$sOut .= '&' . $sBase64 . '-';continue;        }    }return $sOut;}

// 解码function IMAPDeconde($sStr){$sOut = '';$sBase64 = '';$nIndex = 0;$sRegAsis = '/^([^&]+)/';$sReg26 = '/^\&-/';$sRegDecode = '/^\&([A-Za-z0-9+,]+)-?/';$sRegComma = '/,/';

while ($nIndex < strlen($sStr))    {$aTmp = array();$nResult = preg_match($sRegAsis, $sStr, &$aTmp, null, $nIndex);if ($nResult)        {$nIndex += strlen($aTmp[0]);$sOut .= $aTmp[0];continue;        }$nResult = preg_match($sReg26, $sStr, &$aTmp, null, $nIndex);if ($nResult)        {$nIndex += strlen($aTmp[0]);$sOut .= '&';continue;        }$nResult = preg_match($sRegDecode, $sStr, &$aTmp, null, $nIndex);if ($nResult)        {$nIndex += strlen($aTmp[0]);$sBase64 = substr($aTmp[0], 1, strlen($aTmp[0]) - 2);$sBase64 = preg_replace($sRegComma, '/', $sBase64);$nMod = strlen($sBase64) % 4;if ($nMod > 0) $sBase64 .= str_repeat('=', 4 - $nMod);$sBase64 = iconv('UTF-16BE', 'UTF-8', base64_decode($sBase64));$sOut .= $sBase64;continue;        }    }return $sOut;}