System.Uri.HexEscape C# (CSharp) Method

        public static string HexEscape(char character)
        {
            if (character > '\xff')
            {
                throw new ArgumentOutOfRangeException(nameof(character));
            }
            char[] chars = new char[3];
            int pos = 0;
            UriHelper.EscapeAsciiChar(character, chars, ref pos);
            return new string(chars);
        }

        /// <summary>
        /// 编码汉字
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public static string Escape(this string str)
        {
            StringBuilder sb = new StringBuilder();

            foreach (char c in str)
            {
                sb.Append((Char.IsLetterOrDigit(c) || c == '-' || c == '_' || c == '\\' || c == '/' || c == '.') ? c.ToString() : Uri.HexEscape(c));
            }
            return(sb.ToString());
        }