网络编程常用字符串转换函数

public static string StringToHexString(string s, Encoding encode)
        {
            byte[] b = encode.GetBytes(s);//按照指定编码将string编程字节数组
            string result = string.Empty;
            for (int i = 0; i < b.Length; i++)//逐字节变为16进制字符，以%隔开
            {
                result += "%" + Convert.ToString(b[i], 16);
            }
            return result;
        }
        public static string HexStringToString(string hs, Encoding encode)
        {
            //以%分割字符串，并去掉空字符
            string[] chars = hs.Split(new char[] { '%' }, StringSplitOptions.RemoveEmptyEntries);
            byte[] b = new byte[chars.Length];
            //逐个字符变为16进制字节数据
            for (int i = 0; i < chars.Length; i++)
            {
                b[i] = Convert.ToByte(chars[i], 16);
            }
            //按照指定编码将字节数组变为字符串
            return encode.GetString(b);
        }

        /// 

        /// 字符串转16进制字节数组
        /// 
        /// 
        /// 
        public static byte[] strToToHexByte(string hexString)
        {
            hexString = hexString.Replace(" ", "");
            if ((hexString.Length % 2) != 0)
                hexString += " ";
            byte[] returnBytes = new byte[hexString.Length / 2];
            for (int i = 0; i < returnBytes.Length; i++)
                returnBytes[i] = Convert.ToByte(hexString.Substring(i * 2, 2), 16);
            return returnBytes;
        }

        /// 

        /// 字节数组转16进制字符串
        /// 
        /// 
        /// 
        public static string byteToHexStr(byte[] bytes)
        {
            string returnStr = "";
            if (bytes != null)
            {
                for (int i = 0; i < bytes.Length; i++)
                {
                    returnStr += bytes[i].ToString("X2");
                }
            }
            return returnStr;
        }

        /// 

        /// 从汉字转换到16进制
        /// 
        /// 
        /// 编码,如"utf-8","gb2312"
        /// 是否每字符用逗号分隔
        /// 
        public static string ToHex(string s, string charset, bool fenge)
        {
            if ((s.Length % 2) != 0)
            {
                s += " ";//空格
                //throw new ArgumentException("s is not valid chinese string!");
            }
            System.Text.Encoding chs = System.Text.Encoding.GetEncoding(charset);
            byte[] bytes = chs.GetBytes(s);
            string str = "";
            for (int i = 0; i < bytes.Length; i++)
            {
                str += string.Format("{0:X}", bytes[i]);
                if (fenge && (i != bytes.Length - 1))
                {
                    str += string.Format("{0}", ",");
                }
            }
            return str.ToLower();
        }

        ///

        /// 从16进制转换成汉字
        /// 
        /// 
        /// 编码,如"utf-8","gb2312"
        /// 
        public static string UnHex(string hex, string charset)
        {
            if (hex == null)
                throw new ArgumentNullException("hex");
            hex = hex.Replace(",", "");
            hex = hex.Replace("\n", "");
            hex = hex.Replace("\\", "");
            hex = hex.Replace(" ", "");
            if (hex.Length % 2 != 0)
            {
                hex += "20";//空格
            }
            // 需要将 hex 转换成 byte 数组。 
            byte[] bytes = new byte[hex.Length / 2];

            for (int i = 0; i < bytes.Length; i++)
            {
                try
                {
                    // 每两个字符是一个 byte。 
                    bytes[i] = byte.Parse(hex.Substring(i * 2, 2),
                    System.Globalization.NumberStyles.HexNumber);
                }
                catch
                {
                    // Rethrow an exception with custom message. 
                    throw new ArgumentException("hex is not a valid hex number!", "hex");
                }
            }
            System.Text.Encoding chs = System.Text.Encoding.GetEncoding(charset);
            return chs.GetString(bytes);
        }
    }
    
             /// 

        /// 十六进制换算为十进制
        /// 
        /// 
        /// 
        public  int GetHexadecimalValue(String strColorValue)
        {
            char[] nums = strColorValue.ToCharArray();
            int total = 0;
            try
            {
                for (int i = 0; i < nums.Length; i++)
                {
                    String strNum = nums[i].ToString().ToUpper();
                    switch (strNum)
                    {
                        case "A":
                            strNum = "10";
                            break;
                        case "B":
                            strNum = "11";
                            break;
                        case "C":
                            strNum = "12";
                            break;
                        case "D":
                            strNum = "13";
                            break;
                        case "E":
                            strNum = "14";
                            break;
                        case "F":
                            strNum = "15";
                            break;
                        default:
                            break;
                    }
                    double power = Math.Pow(16, Convert.ToDouble(nums.Length - i - 1));
                    total += Convert.ToInt32(strNum) * Convert.ToInt32(power);
                }

            }
            catch (System.Exception ex)
            {
                String strErorr = ex.ToString();
                return 0;
            }


            return total;
        }