What is the difference between Synchronous and Asynchronous ajax request

Every developer want to know about Synchronous vs Asynchronous

Most of the developer often faces this question in interview.
I was also questioned several times so i plan to write a small post so that others can get help.
I found a nice explanation on stackoverflow.

See below explanation-:

Here i found another nice one explanation.

Finally i come to this conclusion

Get directory path in symfony 2.8 and 3.0

Get base path -:


  echo 'path is '.realpath($this->container->getParameter('kernel.root_dir').'/..');

How to shift php array key pair value to top or bottom

MOVE KEY VALUE PAIR TO THE TOP/BOTTOM OF AN ARRAY

<?php
class demo{
   public function arratData(){
      $myArray= array (
                 'bk101' => array (
                                'author' => 'Gambardella, Matthew',
                                'title' => 'XML Developer\'s Guide',
                                'genre' => 'Computer',
                                'price' => '44.95',
                                'publish_date' => '2000-10-01',
                                'id' => 'bk101'
                                  ),
                 'bk102' => array (
                                'id' => 'bk102',
                                'author' => 'Ralls, Kim',
                                'title' => 'Midnight Rain',
                                'genre' => 'Fantasy',
                                'price' => '5.95',
                                'publish_date' => '2000-12-16',
                                'description' => 'A former architect battles corporate zombies...',
                                  ),
                        );
 
    echo '<pre>Actual Array set <br />';
    print_r($myArray);
 
    // call the function move_to_top
    // i want ID of "bk101" should be at top
 
    $top = $this->move_to_top($myArray['bk101'],'id');
 
    echo '<h4>ID of "bk101 will be at top which is at bottom in actual array"</h4>';
    print_r($top);
 
 
    // Now call the function move_to_bottom
    // i want ID of "bk102" should be at bottom which is at top right now
 
    $bottom = $this->move_to_bottom($myArray['bk102'],'id');
 
   echo '<h4>ID of "bk102 will be at bottom which is at top in actual array"</h4>';
    print_r($bottom);
 
 
 
 
   }
 
    public  function move_to_top(&$array, $key) {
        $temp = array($key => $array[$key]);
        unset($array[$key]);
        return $array = $temp + $array;
    }

    public  function move_to_bottom(&$array, $key) {
         
            $temp = array($key => $array[$key]);
            unset($array[$key]);
            return $array = $array + $temp;
    }
}

$a=new demo;
$show_data=$a->arratData();
echo $show_data;
?>

Output

Download File