How to check if the $dateStart and $dateEnd is empty?
<?php
if (isset($_POST['submit'])) {
$leaveR = $_POST['leave'];
$dateStart = $_POST['startDate'];
$dateEnd = $_POST['endDate'];
$leaveReason = $_POST['reason'];
$credits = $_POST['credit'];
$oic = $_POST['oicc'];
if ($leaveR == "" || $dateStart == "" || $dateEnd == "" || $leaveReason == "" ||
$credits == "" || $oic == "") {
echo '<div class="alert alert-danger" role="alert">Fill up all fields</div>';
This partly depends on your javascript code. Is the datepicker defaultly set to the current date or "0000-00-00" for example. Or does it simply return blank.
Comprehensive answer without knowing your javascript initiation of datepicker:
if( isset( $_POST['startDate'] ) && trim( $_POST['startDate'] ) !== "" && trim( $_POST['startDate'] ) !== "0000-00-00" || !isset( $_POST['startDate'] ) ) {
// do something
}