PHP form validate with javascript

Question

I've been at this the whole day. First I tried to validate my form in php but finally gave up. Now I'm trying to validate the form with JavaScript. It works but since I don't know JavaScript at all and have limited knowledge of PHP I really need help please. It is a test and I want to validate that each question has been answered. The field name in the form = php variable/array, can't get this to work in the javascirpt

var x=document.forms["myForm"]["question_{$q_nr}"].value;

. If I just use a text field name it works fine.

The form

<html>
<head>
<?php
session_start();
?>
<script type="text/javascript" src="counter.js"></script>
<script language="JavaScript">
<!--
function validateForm()
{
var x=document.forms["myForm"]["question_{$q_nr}"].value;
if (x==null || x=="")
  {
  alert("First name must be filled out");
  return false;
  }
}
//-->
</script>
</head>

<body>
<?php
if ($_SESSION['auth']) {
$tid = $_GET['tid'];
echo "<span id='counter'></span>";
$sql1="SELECT * FROM ex_question WHERE test_name = '$tid' ORDER BY q_nr";
$result1=mysql_query($sql1);

echo "<form name='myForm' action='http://localhost/index.php?option=com_content&view=article&id=51' onsubmit='return validateForm()' method='post'>";
while($row1 = mysql_fetch_array($result1))
{
    $q_nr=$row1['q_nr'];
    $q_type=$row1['q_type'];
    $question=$row1['question'];
    $option1=$row1['option1'];
    $option2=$row1['option2'];

    echo "<P><strong>$q_nr $question</strong><BR>";
    echo "<img src='images/tests/$pic'>";
    echo "<BR>";
    echo "<BR>";
    echo "</p>";
if ($q_type != 'mr') {
if($option1!="") {
echo "<input type='radio' name='question_{$q_nr}' value='A'>$option1<BR>";
} else {
echo ''; }
if($option2!="") {
echo "<input type='radio' name='question_{$q_nr}' value='B'>$option2<BR>";
} else {
echo ''; }
} else { // else if not <> mr
if($option1!="") {
echo "<input type='checkbox' name='question_{$q_nr}[]' value='A'>$option1<BR>";
} else {
echo ''; } 
if($option2!="") {
echo "<input type='checkbox' name='question_{$q_nr}[]' value='B'>$option2<BR>";
} else {
echo ''; } 
} //if q_type <> mr
} //while row1
echo "First name: <input type='text' name='fname'>";
echo "<input type='submit' value='Submit'>";
echo "</form>";
} //else if now > testend
} //if ses auth
?>

Validating a form using javascript does not ensure that the sent data are good. Infact, a person could always disable javascript and submit the data. — Aurelio De Rosa, Oct 06 '11 at 14:42
`First I tried to validate my form in php but finally gave up. Now I'm trying to validate the form with JavaScript.` I fear that server-side validtion is mandatory, or I can just disable my JS and crack your script;) — Damien Pirsy, Oct 06 '11 at 14:43
Anyway, you accepted an answer on how to validate with php, what's gone wrong in the meantime? http://stackoverflow.com/questions/7672214/validate-form-in-php/7672879#7672879 — Damien Pirsy, Oct 06 '11 at 14:46
@Damien Pirsy Well it does not want to validate the form in the foreach — Wilest, Oct 06 '11 at 14:52

score 1 · Answer 1 · answered Oct 08 '12 at 16:37

why do you think so complicated ?

just use unique ID's for each label, input field, etc ... and check for the innerHTML or value stored; and also you can change the values whenever you want;

btw, your code is messy;

write your code like this:

zone 1: all the js goes here

zone 2: all the html goes here

zone 1:

<script language="text/JavaScript">
//alljs code here

function validate()
{

if( document.getElementById('unique_2').value == null ) document.getElementById('unique_3').innerHTML = 'error1';

if(document.getElementById('unique_4').value == null ) document.getElementById('unique_6').innerHTML = 'error 2';

}

</script>

zone 2:

<form onsubmit="validate()">

all html label and fields go here, like:

<label id="unique_1">label text</label>
<input type="text" id="unique_2" value="" />
<label id="unique_3"></label> this is for the error message

<label id="unique_4">label text</label>
<input type="text" id="unique_5" value="" />
<label id="unique_6"></label> this is for the error message

</form>

score 0 · Answer 2 · edited Oct 07 '11 at 01:04

0

This is simple JQuery validation.

I think you must have both validation if you want to be secured...

p.s. Just add 'required' in class of input if you want to be required...

edited Oct 07 '11 at 01:04

crazyjul

2,519
19
26

answered Oct 06 '11 at 14:55

ikamatovic

43
2
7

score -2 · Answer 3 · answered Oct 06 '11 at 14:41

-2

Well for one thing -- validating on the server side is the way to go.

If you just validate on the client side, it can be futzed with (a lot)

answered Oct 06 '11 at 14:41

Naftali

144,921
39
244
303

All I want to do is validate that each question was answered. If server side is the way to go I'll try again. – Wilest Oct 06 '11 at 14:56
1

@wilest Client side is just a nice touch, server side is a necessity, period. – Damien Pirsy Oct 06 '11 at 15:06

PHP form validate with javascript

3 Answers3