using System;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        string s = new Authentication().EncryptionReview("abcdefg");
    }



    //密码验证
    public class Authentication
    {
        /// <summary>
        /// 加密签字密码，和OA用户名密码加密机制一样
        /// </summary>
        /// <param name="CodeStr"></param>
        /// <returns></returns>
        public string EncryptionReview(string CodeStr)
        {
            double NewCode = 1;
            int CodeLen = 30;
            int CodeSpace = CodeLen - CodeStr.Length;
            int Been = 0;
            string returnstring = "";

            for (int i = 1; i <= CodeSpace; i++)
            {
                CodeStr = CodeStr + Chr(21);
            }

            for (int i = 1; i <= CodeLen; i++)
            {
                Been = CodeLen + Convert.ToInt32(Asc(CodeStr.Substring(i - 1, 1))) * i;
                NewCode = NewCode * Been;

            }
            double NewCodes = double.Parse(NewCode.ToString("0.00"));
            string NewCodee = "";
            NewCode = 0;

            for (int i = 1; i <= Convert.ToString(NewCodes).Length; i++)
            {
                if (Convert.ToString(NewCodes).Length - i > 1) { NewCodee = NewCodee + EncryptionReviewa(Convert.ToString(NewCodes).Substring(i - 1, 3)); }
                else if (Convert.ToString(NewCodes).Length - i == 1) { NewCodee = NewCodee + EncryptionReviewa(Convert.ToString(NewCodes).Substring(i - 1, 2)); }
                else if (Convert.ToString(NewCodes).Length - i == 0) { NewCodee = NewCodee + EncryptionReviewa(Convert.ToString(NewCodes).Substring(i - 1, 1)); }
            }
            for (int i = 20; i <= Convert.ToString(NewCodee).Length - 18; i = i + 2)
            {
                returnstring = returnstring + NewCodee.Substring(i - 1, 1);
            }
            return returnstring;

        }
        private string EncryptionReviewa(string PassStr)
        {
            string CfsCode = "";
            for (int i = 1; i <= PassStr.Length; i++)
            {
                CfsCode = CfsCode + Asc(PassStr.Substring(i - 1, 1));
            }
            return int.Parse(CfsCode).ToString("X");
        }
        private static int Asc(string character)
        {
            if (character.Length == 1)
            {
                System.Text.ASCIIEncoding asciiEncoding = new System.Text.ASCIIEncoding();
                int intAsciiCode = (int)asciiEncoding.GetBytes(character)[0];
                return (intAsciiCode);
            }
            else
            {
                throw new Exception("Character is not valid.");
            }

        }
        private static string Chr(int asciiCode)
        {
            if (asciiCode >= 0 && asciiCode <= 255)
            {
                System.Text.ASCIIEncoding asciiEncoding = new System.Text.ASCIIEncoding();
                byte[] byteArray = new byte[] { (byte)asciiCode };
                string strCharacter = asciiEncoding.GetString(byteArray);
                return (strCharacter);
            }
            else
            {
                throw new Exception("ASCII Code is not valid.");
            }
        }
    }
}