Redirect the user login form to a different url in Drupal

The other day I was tasked with redirecting the Drupal login form to the user account page. On any other form this would work by adding the #redirect tag to the form in a form alter function like this:

// Incorrect method, this doesn't work for the user login forms.
function MYMODULE_form_alter(&$form, &$form_state, $form_id) {
  switch($form_id) {
    case 'user_login_block':
    case 'user_login':
      $form['#redirect'] = 'user';
    break;
  }
}

However, the user login form uses the 'destination' URL parameter which overrides the #redirect in the form. In order to force the user login form and the user login block to redirect I needed to use the destination URL parameter like this:

 
function MYMODULE_form_alter(&$form, &$form_state, $form_id) {
  switch($form_id) {
    case 'user_login_block':
    case 'user_login':
      // Explode the form action and get the query string.
      $url = explode('?', $form['#action']);
      // Replace the query string with the destination I want, in this case the 'user' page.
      $form['#action'] = $url[0] . '?destination=user';
    break;
  }
}