(php) date_parse_from_format

convertDate.php

<?php
/**  
 * convert 20120102 to 2012-1-2
 * 
 * @return string
 */
function convertDate($date) {
	$dateInfo = date_parse_from_format('Ymd', $date);
	return $dateInfo['year'] . '-' . $dateInfo['month'] . '-' . $dateInfo['day']; 
}

date_parse_from_format.php

// refs. http://www.php.net/manual/en/function.date-parse-from-format.php

php > print_r (date_parse_from_format('Ymd', '20120102'));
Array
(
    [year] => 2012
    [month] => 1
    [day] => 2
    [hour] => 
    [minute] => 
    [second] => 
    [fraction] => 
    [warning_count] => 0
    [warnings] => Array
        (
        )

    [error_count] => 0
    [errors] => Array
        (
        )

    [is_localtime] => 
)