namespace test001
{
/**
    对sSource，进行加密、解密操作。
    @param sSource String ：操作的字符串
    @param iFlag int :操作类型 1-加密   2-解密
    @return String :加密或解密后的字符串
     **/
public class password
{
   public password()
   {
   }
   public static string pWord(string sSource,int iFlag)
   {
    if(sSource==null)
     return null;
    if(sSource.Equals(""))
     return "";
    int li_len,i,li_asc,li_rand,li_head;
             string ls_i,ls_code="";
    if(iFlag ==1)
    {
     li_len=sSource.Length;
     Random rdm1 = new Random(~unchecked((int)DateTime.Now.Ticks));
     li_head=(int)(rdm1.NextDouble()*10);
     if(li_head ==0)
      li_head =1;
     for(i=0; i<li_len; i++)
     {
      Random rdm2 = new Random(~unchecked((int)DateTime.Now.Ticks));
      int rand2 =(int)(rdm2.NextDouble() *94);
      if(rand2 ==0)
       rand2 =1;
      li_rand=rand2+32;
      li_asc=Convert.ToInt32(sSource.ToCharArray(i,1)[0]);
      ls_i=((char)(li_asc -i)).ToString();

      if(li_asc+i+li_head>126)
      {
       if(li_rand%2 ==1)
        li_rand=li_rand+1;
       ls_i=((char)(li_rand)).ToString()+((char)(li_asc -i -li_head)).ToString();
      }
      else
      {
       if(li_rand%2 ==0)
        li_rand=li_rand+1;
       ls_i=((char)(li_rand)).ToString()+((char)(li_asc +i +li_head)).ToString();
      }
      ls_code=ls_code+ls_i;
     }
     Random rdm3 = new Random(~unchecked((int)DateTime.Now.Ticks));
     int rand1 =(int)(rdm3.NextDouble()*9);
     if(rand1 ==0)
      rand1 =1;
     ls_code=((char)(rand1*10+li_head+40)).ToString()+ls_code;
    }
    else
    {
     int li_ret;
     li_len=sSource.Length;
     ls_code="";
     li_ret=Convert.ToInt32(sSource.ToCharArray(0,1)[0]) %10;
     for( i=2;i <li_len; i=i+2)
     {
      li_asc=Convert.ToInt32(sSource.ToCharArray(i,1)[0]);
      if(Convert.ToInt32(sSource.ToCharArray(i - 1,1)[0]) %2 ==0)
      {
       ls_i=((char)(li_asc + (i - 1)/2 + li_ret)).ToString();
      }
      else
      {
       ls_i=((char)(li_asc - (i - 1)/2 - li_ret)).ToString();
      }
      ls_code=ls_code+ls_i;
     }
    }
    return ls_code;
   }
}
}