how to set date in form in php code example

Example 1: how to set date in php

// 1. create a date instance
$date = new DateTime;

// 2. set the date using the setDate(year, month, date) method on the
//    $date instance
$date->setDate(1999,02,19);

Example 2: get current date from year input php

$date_input = '2003';
$date_output= date( "Y-m-d", mktime( 0, 0, 0, 1, 1, $date_input ));
//date_output = 2003-01-01