how to call json in php code example

Example 1: json php

//Json Encode

$person = array( 
    "name" => "KINGASV", 
    "title" => "CTO"
); 
$personJSON=json_encode($person);//returns JSON string

//Json Decode

$personJSON = '{"name":"KINGASV","title":"CTO"}';

$person = json_decode($personJSON);

echo $person->name; // KINGASV

Example 2: return json in php

//code igniter
$query="qry";
$query = $this->db->query($query);
$res=$query->result();
return json_encode($res);