update_user_meta() not working

Question

i'm having a trouble with Wordpress, with the function update_user_meta()

I'm trying to update or add a new custom meta value for the user, who already have the custom meta working on the edit profile. But when i do the function update_user_meta() outside the edit-profile.php, just didn't work for me.

I have a page like a page of contact where the form will edit the custom metadata of the profile, in the front side of the wordpress like a normal page of wordpress, but when he submit the form, he just don't update, here is my code:

when the user submit:

function update_termini() {
    $user = wp_get_current_user();
    $userData = array();
    $userData['checkbox'] = intval( $_POST['custom_user_fields_checkbox'] );
    update_user_meta( $user, 'custom_user_fields', $userData );
}
add_action('edit_user_profile', 'update_termini');

Answer 1

wp_get_current_user() returns an object. update_user_meta( $user_id, $meta_key, $meta_value, $prev_value ) accepts user_id as first parameter. Use the following code to get user ID from wp_get_current_user()

update_user_meta( $user->ID, 'custom_user_fields', $userData );

Answer 2

This is the right way to update user meta so you don't mess up your data; the snippet is commented so as to provide more details:

function update_termini( $user_id ) {
//    print_r( $user_id );
//    exit;
// $user_id holds the user ID of the actual user's profile page subjected to the edit.
// That is the right way to do it.


// The comment block right below this very block is an ineffective way as it will only work
// for a current user editing his/her own profile page and why it is not the best way out;

// Using wp_get_current_user() to derive at a user ID as in: $user = wp_get_current_user();
// then, $user->ID; will enable you get the user ID of the CURRENT USER and that is going
// to AFFECT YOUR DATA NEGATIVELY when an administrator for instance edits the profile of
// a user; what will happen then is that the data of the custom field will actually update
// the records of the administrator rather than that of the intended user whos profile in
// being edited by the administrator.

// You can then perform any checks if needed,
    if ( current_user_can( 'edit_user' ) ) {
//      print_r( $_POST );
//      exit;

// And proceed to update the user meta of the actual user's profile page subjected to the edit;
// it may or may not be the current user.
// This way, you are sure to update the right field with right information.

// For the purpose of this update, it is assumed the name of our newly added custom field
// is custom_user_fields_checkbox.
        update_user_meta( $user_id, 'custom_user_fields_checkbox', $_POST['custom_user_fields_checkbox'] );
    }
}
add_action( 'edit_user_profile', 'update_termini' );