Validating Forms Php/javascript

[64]

I've made a basic captcha function that generates a random 5-digit code that the user has to input in order to prove that they are human. Basic stuff. However, I want it to load a javascript function to validate the captcha before the form is funny submitted.

Here's the Javascript:

<script type='text/javascript'>
function check(form){
	if(form.cap.value != <?php echo($c); ?>){
		alert("You must enter the captcha code.");
		form.cap.focus();
		return true;
	} else {
	return true;
	}
}
</script>

The correct captcha string is $c, by the way. Here's my form HTML:

<form name="upf" enctype="multipart/form-data" action=\"\" method="post">

	..Other input shit, blah blah..

	<input name="cap" type="text" maxlength="5"/>
	<input type="submit" value="Upload" name="upload" onclick="return check(document.upf);"/>
</form>

Now, I don't know the least bit of Javascript, at all, so for all I know this could be a very simple problem. I also don't know if the way I'm implementing the PHP variable into the function is correct.

[WoogieNoogie]

You seem to be doing it the correct way...however, without a proper CAPTCHA, bots will read the line of characters and input it into the correct field. I know, it happened to me :(

[64]

Well eventually I'll replace it with like, a question or math problem. But that still doesn't help the fact that my code doesn't work.

[urbn]

You can do it through PHP easier.

Also, you can use PHP to generate an image with the text on, which simpler bots can't read at all (you need the fuzziness or something similar for near all bots to not read it).