.net加密函数

 public static string EncryptPassword(string PasswordString,string PasswordFormat )
     {
         string dd="error";
         if (PasswordFormat=="SHA1")
          {
                dd=System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(PasswordString ,"SHA1");
           }
         else if(PasswordFormat=="MD5")
          {
              dd = System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(PasswordString, "MD5");
           }
   
           return dd;
     }