How to check if the user is guest in a form

Question

I have a form in a page, so what I want to do is to check wether the user is a guest or a logged user and depending of that add an additional field to a guest, but hide it for the logged user, should this be done in the code of the form or there are some built-in settings for that behaviour?

Answer 1

Can you please elaborate the question. As per the understanding you have to use this condition to check the user login status. Since you have to use it in a form, you can implements with hook_form_FORM_ID_alter().

Use this code to check.

if (user_is_logged_in()) {
    echo "Logged In";
}
else {
    echo "Not logged in";
}

Edited:

Example for user_profile_form alter. FORM_ID = user_profile_form

/**
 * Implements hook_form_FORM_ID_alter().
 */
function mymodule_form_user_profile_form_alter(&$form, &$form_state, $form_id) {
}

To find form id add this in your custom module.

/**
 * Implements hook_form_alter().
 */ 
function mymodule_form_alter(&$form, &$form_state, $form_id) {
  print_r($form_id);
}

When you visit the page the form is on, the form_id will be displayed.

print_r($form); , you can see all details of a form, like form ID, field names of a form etc.

Also you can inspect the form and find the form id

<form enctype="multipart/form-data" action="/user/288/edit" method="post" id="user-profile-form" accept-charset="UTF-8">

Here id="user-profile-form", in order to use it in code replace hiphen (-) with undescore(_)

 user-profile-form => user_profile_form