WordPress Custom Hook with Class method

You can use an anonymous function with PHP’s use statement like so:

function mycars($mycarsclass){
     
    $args = array(
    'car1' => 'Volvo',  
    'car2' => 'Toyota'
    ); 
    
    $mycarsclass->add_node($args);  
}

add_action('mycarsaction', function () use ($mycarsclass) {
    mycars($mycarsclass);
});
do_action('mycarsaction');

or declare a separate function and pass that:

function mycars($mycarsclass){
     
    $args = array(
        'car1' => 'Volvo',  
        'car2' => 'Toyota'
    ); 
    
    $mycarsclass->add_node($args);  
}

function mycars_mycarsclass() {
    $mycarsclass = new mycarsclass();
    mycars($mycarsclass);
}

add_action('mycarsaction', 'mycars_mycarsclass');
do_action('mycarsaction');