下面列出c#中MD5加密和sha1加密的方法，以供參考

using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Web;

namespace MD5.Helper
{
    public static class EncryptHelper
    {

        /// <summary>
        /// MD5加密：
        /// 16位小寫
 

        /// 16位大寫
        /// 32位小寫
        /// 32位大寫
        /// </summary>
        /// <param name="strText"></param>
        /// <param name="type"></param>
        /// <returns></returns>
        public static string GetMD5(string strText,MD5Type type)
        {
            string
 
 strReturn = string.Empty;

            MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();

            byte[] result = md5.ComputeHash(Encoding.UTF8.GetBytes(strText));

            if (type == MD5Type.Bit16Lower)
            {
                strReturn = BitConverter.ToString(result, 4
 
, 8).Replace("-", string.Empty).ToLower();
            }
            if (type == MD5Type.Bit16Upper)
            {
                strReturn = BitConverter.ToString(result, 4, 8).Replace("-", string.Empty).ToUpper();
            }
            if (type == MD5Type.Bit32Lower)
            {
                strReturn = BitConverter.ToString(result).Replace("-", string.Empty).ToLower();
            }
            if (type == MD5Type.Bit32Upper)
            {
                strReturn = BitConverter.ToString(result).Replace("-", string.Empty).ToUpper();
            }


            return strReturn;
        }


        /// <summary>
        /// Base64加密
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public static string GetBase64(string str)
        {
            byte[] strArray = Encoding.Default.GetBytes(str);
            return Convert.ToBase64String(strArray);
        }

        /// <summary>
        /// sha1加密
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public static string GetSha1(string str)
        {
            var buffer = Encoding.UTF8.GetBytes(str);
            var data = SHA1.Create().ComputeHash(buffer);

            string result= BitConverter.ToString(data).Replace("-",string.Empty).ToLower();

            return result;
        }




    }

    public enum MD5Type
    {
        Bit16Upper,//16位大寫
        Bit16Lower,//16位小寫
        Bit32Upper,//32位大寫
        Bit32Lower,//32位小寫
    }
}