JavaScript and PHP

[ksoong]

Hi everyone. i'll also be posting this in the javascript forum.

I have a bunch of check boxes in my html. the name list[] was given so that the PHP script it would be directed to could grad the values out of the checkbox using an array.

<form name=myform>
<input type=checkbox name=list[] value=&quot;1&quot;>1<br>
<input type=checkbox name=list[] value=&quot;2&quot;>2<br>
<input type=checkbox name=list[] value=&quot;3&quot;>3<br>
<input type=checkbox name=list[] value=&quot;4&quot;>4<br>
<input type=checkbox name=list[] value=&quot;5&quot;>5<br>
</form>

as you can see the name is list[]

But how can i reference the list[] checkbox using javascript? if anyone has experience doing this.

here is my code so far which i've experiented with.

<SCRIPT LANGUAGE=&quot;JavaScript&quot;>
<!-- Begin

var field=document.myform.elements[0];
alert(document.myform.elements[&quot;list[]&quot;][0].name);
// tried document.myform.list[][0].name
// tried document.myform.'list[]'[0].name
// tried document.myform.elements[0][0].name
// End -->
</script>


any help would be appreciated thanks.

 

[GIGN]

Get rid of the square brackets, it is confusing the browser. Just call the collection list, then list[0].value etc will work.



;-)

 

[rycamor]

bangers-- unfortunately that will not work for PHP, even though it works for Javascript.

The only real solution I can see here is to explicitly set your array, instead of &quot;letting it index itself&quot;:

<form name=myform method=post action=&quot;phpinfo.php&quot;>
<input type=checkbox name=list[1] value=&quot;1&quot;>1<br>
<input type=checkbox name=list[2] value=&quot;2&quot;>2<br>
<input type=checkbox name=list[3] value=&quot;3&quot;>3<br>
<input type=checkbox name=list[4] value=&quot;4&quot;>4<br>
<input type=checkbox name=list[5] value=&quot;5&quot;>5<br>
<input type=&quot;submit&quot; onclick=&quot;clickit()&quot;>
</form>

This will produce an array that PHP can deal with, while the syntax I give you here for Javascript will allow Javascript to treat each one as a unique name

<SCRIPT LANGUAGE=&quot;JavaScript&quot;>

function clickit(){
alert(document.myform('list[1]').name);
alert(document.myform('list[2]').value);
//etc...
}
//  End -->
</script>

This syntax makes Javascript delimit the form element name with a different character than the element's own index delimiter. Using single quotes is generally the way to tell a programming language not to try to interpret what is inside them, but to simply treat it as a string.

The reason I direct the form to phpinfo.php is so that you can create a page called phpinfo.php with:

<?php
phpinfo();
?>

When you submit your form to this page, you will see your array of checkbox variables (in the PHP Variables section). This time the array will not be dynamic: if you check the first, third, and fifth checkbox you will have variables $list[1], $list[3], and $list[5], instead of $list[0], $list[1], and $list[2].

Catch my drift?

P.S. Also, I would steer clear of using form element names like &quot;list&quot;, because it sounds to me like it could be a reserved word, either in Javascript or PHP. It shouldn't technically be a problem, but I find it good practice to make my form element names and variable names as unique and descriptive as possible, thereby avoiding the likelihood of namespace conflicts.

HTH ;-)