я попробовал это код
$temp = "1|<select class='form-control selectpicker' id='sel_date'
onchange='return GetSessionData(\"2\")'>
<option>Select Date</option>
<option value='2016/01/08'>08-Jan-2016</option>
<option value='2016/01/09'>09-Jan-2016</option>
<option value='2016/01/10'>10-Jan-2016</option>
<option value='2016/01/11'>11-Jan-2016</option>
<option value='2016/01/12'>12-Jan-2016</option>
<option value='2016/01/13'>13-Jan-2016</option></select>";
$_date_pattern_two = "/<option value=(/([a-zA-Z]+) (\d+)/>(.*?)/<\/option>";
preg_match_all($_date_pattern_two, $temp, $_date_match_two);
var_dump($_date_match_two);exit;
the out put я want array содержит все даты. здесь $_date_match_two = ['08-Jan-2016','09-Jan-2016','10-Jan-2016','11-Jan-2016',..];
Вот ваш ответ: -
preg_match_all("/\d{4}\/\d{2}\/\d{2}/", $temp, $match);
echo '<pre>'; print_r($match[0]);exit;
выход: -
Array
(
[0] => 2016/01/08
[1] => 2016/01/09
[2] => 2016/01/10
[3] => 2016/01/11
[4] => 2016/01/12
[5] => 2016/01/13
)