Is it possible call a function, whatever the parameter isset or not,
how to do it?
select();
select($response_message);
function select($response_message) {
  ....
}
Is it possible call a function, whatever the parameter isset or not,
how to do it?
select();
select($response_message);
function select($response_message) {
  ....
}
 
    
     
    
    For PHP, when you declare the function, put in a default value
function select($response_message = 'whatever') {
    ....
}
At this point, select() and select('whatever') run the same thing.
As for javascript, that process is a little more involved