form submit hook handler not getting called in drupal I have Drupal 7 site. It has custom module named say myproducts. This module has following hook 

function myproducts_form_alter(&amp;$form, &amp;$form_state, $form_id) {

if(isset($form_id) &amp;&amp; $form_id=='product_node_form')
{
   $form['#submit'][] = 'myform_form_submit';
}

}


function myform_form_submit(){
 echo 'test submit handler'; exit();
 }


But `myform_form_submit` is not getting called. 

Any help highly appreciated.
The submit for the node form is attached to a specific button, so something like this should work:

$form['actions']['submit']['#submit'][] = 'myform_form_submit';