cannot get checkboxes value using drupal form api - drupal

Question

i have form in drupal which uploads images and has got few checkboxes in it.
Here is the form:
$form['checklist_fieldset'] = array(
'#type' => 'fieldset',
'#title' => t('Check List'),
'#collapsible' => FALSE,
'#collapsed' => FALSE,
);
$form['checklist_fieldset']['heating'] = array(
'#type' => 'checkboxes',
'#title' => t('Heating options'),
'#options' => array(
'0' => t('Yes'),
'1' => t('No')
),
'#description' => t('Heating details.')
);
and here is my submit function where i am processing image upload and grabbing the checkboxes value as well. I am getting the success message and image is getting uploaded but not getting the value of check boxes.
function property_add_view_submit($form,&$form_state){
$validators = array();
if($file = file_save_upload('p_file1',$validators,file_direcotry_path)){
$heating = array_keys($form_state['values']['heating']);
drupal_set_message(t('Property Saved! '.$heating));
dpm( $form_state['values']['heating']);
}

Answer 1

When you use #options on a FAPI element the value passed to the $form_state is the array key, so you don't need to use array_keys().
I'm not sure why you're using checkboxes for a yes/no, usually one would use a simple checkbox element. However if that's really what you want to do:
Your #options can't contain on option with 0 as the array key, it will be automatically filtered out and you'll never know if that option has been checked.
You should use $heating_options_chosen = array_filter($form_state['values']['heating'] to get the selected checkbox options.
I honestly think your code should look like this though:
$form['checklist_fieldset']['heating'] = array(
'#type' => 'checkbox',
'#title' => t('Heating options'),
'#options' => array(
'1' => t('Yes'),
'0' => t('No')
),
'#description' => t('Heating details.')
);
$heating_checked = $form_state['values']['heating'] == 1;

Answer 2

If I have checkbox Friends and options are like
[ ] abc
[ ] def
[ ] ghi
[ ] jkl
And I want to know which options user have marked, then use below function.
if ($form_state->getValue('friends') != NULL) {
foreach ($form_state->getValue('friends') as $key => $value) {
if ($value != 0) {
$friends = $friends . ", " . $key;
$friends = substr_replace($friends, "", 0, 1);
}
}
}
If user has chosen abc and ghi then you will get 1,3 as result in $friends
If you wanted to know the value then use $friends = $friends.", ".$value;
it worked for me..hope it will help you as well :)