PHP isset not working with checkbox

Question

I have a form where people need to submit information. This part of code is not working how I want it and I don't know why..

if (!isset($_POST['maandag']) && !isset($_POST['dinsdag']) && !isset($_POST['geenvoork']))
{
    echo "Je bent vergeten in te vullen wanneer je aanwezig bent.";
}

the posts do work in the rest of the form, and are correct. What I want is to check if those 3 checkboxes are not checked. What am I doing wrong?

Solution 1

If they are in your form then they will be set. You likely want to check if they are false. Here's what it is for one, you can combine the others:

if( !isset($_POST['maandag']) || !$_POST['maandag'] ) { 
     // do something
}

Secondly the code as is means that you'll only get the message if none of the checkboxes are set. I'm not certain, but if you're trying to throw an error message don't you want it if any of them are not set? In which case you need || (or) not && (and).

Solution 2

You can try doing a print_r($_POST) and see what the values of the fields are. That might help you determine what is going on with your submission/field values.

Solution 3

i thing ur coding make complicate.,,

try like

<input type="checkbox" name="test[]"  value="1"/>
<input type="checkbox" name="test[]" value="2"/>
<input type="checkbox" name="test[]" value="3"/>

submit the value and get the result

Comments

[Marc B]

empty() is not reliable. if the checkbox's value on the browser side is '0', empty() will be true. Any value in PHP which can be cast to an empty string counts as empty().

[Deep Frozen]

It should be able to check if all 3 checkboxes aren't checked. If they aren't checked, show the message. if 1 or more are checked, don't show it. Anyway, this worked: if (!isset($_POST['maandag']) && !$_POST['maandag'] && !isset($_POST['dinsdag']) && !$_POST['dinsdag'] && !isset($_POST['geenvoork']) && !$_POST['geenvoork'])

[Deep Frozen]

@yi_H it may be ugly, but it works ;) i'll try to optimize another day.. main thing for now is that it works :D

[Cr_U]

I think it is still relevant as the solution and fucntion itself is not outdated. Besides someone could find it useful not having to repeat the same test all over again. I almost always use google to find the solutions and then look through the first few answers...