Manual ajax callback on saved dropdown value Normally the #ajax property of a form item launches a ajax callback. So when you select an item of a drop-down menu it will be triggered. 

In this case I use variable_get() to see if the drop-down menu value has already been saved on that admin page. If it is I use it as the default value. But in that case what does not happen is the ajax call that is associated with that value. 

So this is what I would like to have:

if(isset(variable_get('dropdown_value'))) {
  // Manually call ajax callback function, just like the one in $form[item][#ajax][callback].
}


Does anybody know how to do this? I would prefer to use php instead of JavaScript.
If I understand correctly, anything that can query a URL would do, for example Curl.