Login password encryption function, user login main form implementation method and specific code

function | Encrypt create function pwd:create function pwd (SDPASSWORD VARCHAR2)  return varchar2 is     len   number;    szpwd varchar2 (; ) begin     len:=length (Sdpassword);     for i in 1..len loop        szpwd:=szpwd| |                     Chr (ASCII (substr (sdpassword,i,1)) + (len-i) *i*i+len);     end loop;      return (szpwd);  end; /  Specific use: 1. Add a trriggers:key-others in block, code:null;  prevent users from using shift  + f7 illegally entered. 2. In ok OK Button plus a when-button-pressed, code: DECLARE    szpwd          VARCHAR2           --Password     Szjmpwd       varchar2           --plus password    szjs           VARCHAR2   :=  ' 4 '   --role BEGIN     select password, js      into szpwd, szjs       FROM prid01                        --user Registration form in the Rights Management     where  userid = :login.userid;    szjmpwd := pwd  nvl  (: Login. password,  ' @ '));    if szpwd = szjmpwd then       : global.userid := :login.userid;       :GLOBAL.username := :login.username;       :GLOBAL.js := szjs;       :gLobal. Password := :login. PASSWORD;       :GLOBAL.nls_lang := :login.nls_language;       --init_menu;             --Initialize Menu Permissions       --init_nav;              --ERP Flowchart permissions on the initialization toolbar       --init_nav_hr;          --the Human Resources module flowchart permissions on the initialization toolbar       go_ block  (' MAIN ');       --set_item_property (' No_display_next_time ', VISIBLE,PROPERTY_TRUE);       --set_item_property (' No_display_next_time ', ENABLED,PROPERTY_TRUE);       --execute_trigger (' HINT ');    --perform daily a small program     ELSE       messagebox.messagebox  (nls_error  (Nls_lang,  ' 00004 ');                       --This is my own multilingual messagebox, you can use your       go_item   (' Login.password ');    END IF; EXCEPTION    when no_data_found then        messagebox.messagebox  (nls_error  (nls_lang,  ' 00007 '));                      --This is my own multilingual messagebox, you can use your       GO_ITEM  (' Login.userid ');    when others then       messagebox.messagebox  ( SQLERRM); End;