Automatically creates variables with the same name as the key in the POST array

automatically_creates_variables_with_the_same_name_as_the_key_in_the_POST_array.php

<?php
$username=$_POST["username"];
$age=$_POST["age"];
etc.
?>

<?php
$expected=array('username','age','city','street');
foreach($expected as $key){
    if(!empty($_POST[$key])){
        ${key}=$_POST[$key];
    }
    else{
        ${key}=NULL;
    }
}
?>