using System;
using System.Text.RegularExpressions;
using System.Text;

namespace Sog
{
    public static class StringUtils
    {
        /// <summary>
        /// 判断字符串是否是合法的email地址
        /// 每个公司的邮箱格式不一定一样，去掉算了
        /// </summary>
        /// <param name="email"></param>
        /// <returns></returns>
        public static bool IsValidEmailAddress(string email)
        {/*
            String strExp = @"^([A-Za-z0-9]{1}[A-Za-z0-9_]*)@([A-Za-z0-9_]+)[.]([A-Za-z0-9_]*)$";

            Regex r = new Regex(strExp);
            Match m = r.Match(email);

            return m.Success;
            */

            return true;
        }

        public static string ToHexString(byte[] bytes)
        {
            string hexString = string.Empty;
            if (bytes != null)
            {
                StringBuilder strB = new StringBuilder();
                for (int i = 0; i < bytes.Length; i++)
                {
                    strB.Append(bytes[i].ToString("X2"));
                }
                hexString = strB.ToString();
            }
            return hexString;
        }

        public static string ToHexString(byte[] bytes, int length)
        {
            string hexString = string.Empty;
            if (bytes != null)
            {
                StringBuilder strB = new StringBuilder();
                for (int i = 0; i < bytes.Length && i < length; i++)
                {
                    strB.Append(bytes[i].ToString("X2"));
                }
                hexString = strB.ToString();
            }
            return hexString;
        }

        public static byte[] HexStringToBytes(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;
        }
    }
}