Javascript Hell Help

[Anon]

I'm trying to use javascript to check the contents of a form on submit (to ensure theres content) prior to insertion to a database. Basically I opended the page in dreamweaver4 and attached the javascript validation behaviour to the form and set 'required' for the following $strings:

$title
$problem
$solution
$author

This seems to almost work, if theres no data in $problem or $solution or $author then it sticks an alert up to say so.

However, it still lets $title go through, even though its clearly included in the 'onsubmit' script.

The second problem is that if a space is put in it allows it to continue (e.g. if $problem =' '). I've tried using trim to get rid of the space but it still lets it through?

Can anyone please shed any light on this before I pull all of my hair out?

[wombatee]

Why don't you post the javascript so we can see it? I'll take a look for you. Also, just so you know, you can't rely on javascript form validation. A browser that does not support javascript could easily get away with submitting a blank form.

Cheers!
http://www.drinknation.com

[Anon]

1. If you want to check whether a string is empty, you'd better use

if(str.length==0)

2. JavaScript support PERL-style Regular Expression Match. For example, if your want to find out whether there are non-white-space characters in a string, you can use.

var pattern=/\S+/;
var title = "HELLO";
var nonEmptyString = pattern.test(title);

You can find out more detailed description on PCRE at http://www.php.net/preg_match. For detailed description on Javascript, please check DOM (Document Object Model) related book. My reference book is "Dynamic HTML -- The Definitive Reference" published by OReilly; it is a MUST HAVE book for all web-based developer.

[Anon]

Hi and thanks, not sure if you wanted the whole page or just bits concerned. Heres the script as created by dreamweaver etc.:

<script language="JavaScript">
<!--
function MM_findObj(n, d) { //v4.0
var p,i,x; if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[n];
for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers.document);
if(!x && document.getElementById) x=document.getElementById(n); return x;
}

function MM_validateForm() { //v4.0
var i,p,q,nm,test,num,min,max,errors='',args=MM_validateForm.arguments;
for (i=0; i<(args.length-2); i+=3) { test=args[i+2]; val=MM_findObj(args);
if (val) { nm=val.name; if ((val=val.value)!="") {
if (test.indexOf('isEmail')!=-1) { p=val.indexOf('@');
if (p<1 || p==(val.length-1)) errors+='- '+nm+' must contain an e-mail address.\n';
} else if (test!='R') {
if (isNaN(val)) errors+='- '+nm+' must contain a number.\n';
if (test.indexOf('inRange') != -1) { p=test.indexOf(':');
min=test.substring(8,p); max=test.substring(p+1);
if (val<min || max<val) errors+='- '+nm+' must contain a number between '+min+' and '+max+'.\n';
} } } else if (test.charAt(0) == 'R') errors += '- '+nm+' is required.\n'; }
} if (errors) alert('The following error(s) occurred:\n'+errors);
document.MM_returnValue = (errors == '');
}
//-->
</script>

and heres the bit for the submit

<input type="submit" name="submit" value="Submit" onClick="MM_validateForm('title','','R','problem','','R','author','','R','solution','','R');return document.MM_returnValue">

Again, the title although required will slip through if empty.

I had riginally got round this and the " " issue with the following:
if(isset($submit)):
$title = trim($title);
$title = nl2br($title);
$title = addslashes($title);
$problem = trim($problem);
$problem = nl2br($problem);
$problem = addslashes($problem);
$solution = trim($solution);
$solution = nl2br($solution);
$solution = addslashes($solution);
$author = trim($author);
$author = addslashes($author);
if (($title)=="") {die("<br><h2>You must provide a title!</h2>");}
if (($problem)=="") {die("<br><h2>You must provide a problem!</h2>");}
if (($solution)=="") {die("<br><h2>You must provide a solution!</h2>");}
if (($author)=="") {die("<br><h2>You must provide an author!</h2>");}

----mysql insert queries----

I've now changed the if statements to:

<SCRIPT>
<?php

if (($title)=="") {$message="Title";

echo ("alert (\"The following error occured\n Title required\");");}

if (($problem)=="") {$message="Problem";

echo ("alert (\"The following error occured\n Problem required\");");}

if (($solution)=="") {$message="Solution";

echo ("alert (\"The following error occured\n Solution required\");");}

if (($author)=="") {$message="Author";

echo ("alert (\"The following error occured\n\rAuthor required\");");}

// wrong!
?>
</SCRIPT>

Wich sort of works but is messy.

If theres anything you can suggest it would be appreciated.