$.ajax how to use code example

Example 1: $.ajax({

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>jQuery.post demo</title>
  <script src="https://code.jquery.com/jquery-1.10.2.js"></script>
</head>
<body>
 
<form action="/" id="searchForm">
  <input type="text" name="s" placeholder="Search...">
  <input type="submit" value="Search">
</form>
<!-- the result of the search will be rendered inside this div -->
<div id="result"></div>
 
<script>
// Attach a submit handler to the form
$( "#searchForm" ).submit(function( event ) {
 
  // Stop form from submitting normally
  event.preventDefault();
 
  // Get some values from elements on the page:
  var $form = $( this ),
    term = $form.find( "input[name='s']" ).val(),
    url = $form.attr( "action" );
 
  // Send the data using post
  var posting = $.post( url, { s: term } );
 
  // Put the results in a div
  posting.done(function( data ) {
    var content = $( data ).find( "#content" );
    $( "#result" ).empty().append( content );
  });
});
</script>
 
</body>
</html>

Example 2: $.ajax example

class DB {
		private $host = 'localhost';
		private $user = 'root';
		private $password = '';
		private $db_name = 'library';
		public $conn;
		public function connect() {
			$this-> conn = new mysqli($this-> host, $this-> user, $this-> password, $this-> db_name);
					
			return $this -> conn;

		
	}

}