public static string Escape(string s)         {             StringBuilder sb = new StringBuilder();             byte[] ba = System.Text.Encoding.Unicode.GetBytes(s);             for (int i = 0; i < ba.Length; i += 2)             {                 if (ba[i + 1] == 0)                 {                     //数字,大小写字母,以及"+-*/._"不变                     if (                           (ba[i] >= 48 && ba[i] <= 57)                         || (ba[i] >= 64 && ba[i] <= 90)                         || (ba[i] >= 97 && ba[i] <= 122)                         || (ba[i] == 42 || ba[i] == 43 || ba[i] == 45 || ba[i] == 46 || ba[i] == 47 || ba[i] == 95)                         )//保持不变                     {                         sb.Append(Encoding.Unicode.GetString(ba, i, 2));                     }                     else//%xx形式                     {                         sb.Append("%");                         sb.Append(ba[i].ToString("X2"));                     }                 }                 else                 {                     sb.Append("%u");                     sb.Append(ba[i + 1].ToString("X2"));                     sb.Append(ba[i].ToString("X2"));                 }             }             return sb.ToString();         }