How do I save Multiple fields in a meta box?

Question

Currently I am doing

    public function prfx_meta_save ($post_id){

    if (isset( $_POST[ 'firstname'])){
        update_post_meta($post_id, 'firstname', $_POST[ 'firstname']);
    }
    if (isset( $_POST[ 'lastname'])){
        update_post_meta($post_id, 'lastname', $_POST[ 'lastname']);
    }
    if (isset( $_POST[ 'sex'])){
        update_post_meta($post_id, 'sex', $_POST[ 'sex']);
    }
}

But I would like to somehow loop over all the post values (Not just the ones here) and save them all. So if I add more fields to my Meta Box it should save them without me having to add another update_post_meta

Thanks for the help

Answer 1

I would suggest you define a field names property on your class:

class your_class {
    private $_fields = array(
        'firstname',
        'lastname',
        'sex',
    );

    public function prfx_meta_save ( $post_id ) {

    }
}

Now you can fully abstract your save handler:

foreach ( $this->_fields as $field ) {
    if ( ! isset( $_POST[ $field ] ) )
        continue;

    $value = ( string ) $_POST[ $field ];
    $value = wp_unslash( $value ); // WP adds slashes to all request data
    $value = sanitize_text_field( $value ); // Fix invalid UTF-8, strip tags & line breaks

    update_post_meta( $post_id, $field, $value );
}