[Javascript] regex example & code sample

[shawn_milochik at godivachoc.com]

I'm glad to have received so many replies from the group already.  I'm
going to be so bold as to post some of my code on my first day of
membership.

This is a function for validating a new password, and it happens to be
pretty heavily commented, because I wrote it for a non-programmer
for him to use in an existing page.  It is designed to be added into the
<form> tag as follows:
onsubmit="if (validatePass('frmCheckPass', 'txtOldPassword',
'txtNewPassword1', 'txtNewPassword2') == false){ return false;}"

The purpose of this is that the existing page could not be modified much,
as it will be regularly updated when the vendor (MicroStategy) comes
out with new releases of the code, and we needed to be able to easily put
this functionality back in.

I am posting this to the group because it has some basic regex stuff in it.
I am also going to post another script later, which I use
to show the current time in various countries around the world on an HTML
page, using only Javascript.  I hope someone finds
this stuff interesting or useful.

Comments/improvements welcome.


Shawn



         //password validation.js
         function validatePass(formName, oldPass, newPass1, newPass2){
            //function written on September 18th, 2003
            //by Shawn Milochik  Shawn_Milochik at godivachoc.com
            //
            //Revisions:  none
            //

            //declare variables we will use
            var returnValue = true;  //will decide whether or not to submit
the form

            var strOldPass = eval('document.' + formName + '.' + oldPass +
'.value');
            var strNewPass1 = eval('document.' + formName + '.' + newPass1
+ '.value');
            var strNewPass2 = eval('document.' + formName + '.' + newPass2
+ '.value');
            var errMessage = '';

            alert(strNewPass1 + ', ' + strNewPass2);

            var minLength = 7; // change this to change the minimum
password length
            var strUID = document.location + ''; //get the querystring from
the browser so we can get the Uid

            //Time-limited test stuff
            //replace the actual querystring with the sample
            //pulled from the real page
            if (new Date('9/26/2003 15:00:00') > new Date()){
               alert('testing mode, using fake querystring');
               strUID =
'http://gebis/mstr7/ChangePassword.asp?Server=GDRDWEB01&Project=GEBIS+%28Production%29&ProjectId=7FFAF9AC11D4F601500083903038D204&Port=0&Uid=dwuser&UMode=1';
            }




            //get the Uid from the querystring, and put it in strUID
            //of the Uid in the querystring.
            strUID = strUID.replace(/^.*\&Uid=(\w+)\&.*$/, "$1");

            //  Regular Expression translation for above:
            //       ^ = beginning of the line
            //       . = any character
            //       * = any number of the preceeding value, including zero
            //       \& = &  (& is a special character, and needs to be
escaped)
            //       Uid = find the string "Uid"
            //       \w = a word character (a-z, A-Z, 0-9, _)
            //       + = one or more consecutive positions
            //       \& = &  (& is a special character, and needs to be
escaped)
            //       . = any character
            //       * = any number of the preceeding value, including zero
            //       $ = the end of the line
            //
            //       Using parenthesis around part of the expression allows
us to use
            //       the matching text in the replace function.  In this
case, (\w+)
            //       allowed us to return whatever \w+ matched as $1.  If
we had used
            //       another set of parenthesis, we could refer to the
second one as
            //       $2, and so on.
            //
            //See "Mastering Regular Expressions" by Jeffrey Friedl for all
this and more.
            //



            //**********************************************************
            //  Rule:  Must contain both upper and lower case
            //**********************************************************
            //Check for all lower-case
            if (strNewPass1.toLowerCase() == strNewPass1){
               //alert('New password must contain at least one upper-case
character.');
               errMessage = errMessage + '\n' + 'New password must contain
at least one upper-case character.';
               returnValue = false;
            }

            //Check for all upper-case
            if (strNewPass1.toUpperCase() == strNewPass1){
               //alert('New password must contain at least one lower-case
character.');
               errMessage = errMessage + '\n' + 'New password must contain
at least one lower-case character.';
               returnValue = false;
            }


            //**********************************************************
            //  Rule:  password does not match the user name
            //**********************************************************
            if (strNewPass1 == strUID){
               alert('New password may not be the same as your user ID.');
               returnValue = false;
            }


            //**********************************************************
            //  Rule:  new password is the same in both password boxes
            //**********************************************************
            if (strNewPass1 != strNewPass2){
               alert('New passwords do not match.');
               returnValue = false;
            }

            //**********************************************************
            //  Rule:  password is not the same as the old
            //**********************************************************
            if (strNewPass1 == strOldPass){
               alert('New passwords may not be the same as the old one.');
               returnValue = false;
            }


            //**********************************************************
            //  Rule:  password is not blank
            //**********************************************************
            if (strNewPass1 == ''){
               alert('New password may not be left blank.');
               returnValue = false;
            }


            //**********************************************************
            //  Rule:  password meets minimum length requirements
            //**********************************************************
            if (strNewPass1.length < minLength){
               alert('New password may not less than ' + minLength + '
characters long.');
               returnValue = false;
            }

            //**********************************************************
            //  Rule:  password does not contain the name of a Campbell
brand
            //**********************************************************
            if
(strNewPass1.match(/((arnotts|campbell|franco|godiva|homepride|pace|prego|stockpot|swanson|v-?8|pepperidge|goldfish))/)){
               alert('New password may not contain the name of a Campbell
brand.');
               returnValue = false;
            }


            //**********************************************************
            //  Rule:  password contains at least one letter
            //**********************************************************
            if (strNewPass1.match(/^[0-9]+$/)){
               alert('New password must contain both letters and
numbers.');
               returnValue = false;
            }

            //**********************************************************
            //  Rule:  password contains at least one digit
            //**********************************************************
            if (strNewPass1.match(/^[a-zA-Z]+$/)){
               //alert('New password must contain both letters and
numbers.');
               errMessage = errMessage + '\n' + 'New password must contain
both letters and numbers.';
               returnValue = false;
            }

            //**********************************************************
            //  Rule:  password contains no spaces, tabs, etc
            //**********************************************************
            if (strNewPass1.match(/\s/)){
               //alert('New password may not contain spaces.');
               errMessage = errMessage + '\n' + 'New password may not
contain spaces.';
               returnValue = false;
            }


            if (returnValue == false){ alert(errMessage); }

            //if this returns false to the onSubmit() function within
            //the <form> tag, then the form submission will be cancelled
            return returnValue;

         }





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