Нажатие кнопки не отображает содержимое

 

  var currentDate = new Date()
	var day = currentDate.getDate()
	var month = currentDate.getMonth() + 1
	var year = currentDate.getFullYear()
	document.getElementById('date').innerHTML =("<b>" + day + "/" + month + "/" + year + "</b>");

$(document).ready(function(){
	$('#btn_submit').click(function(){
		var descriptionO =$('#descriptionO').val();
		var PurchaseO = $('#PurchaseO').val;
		var total = $('#total');
		var notes = $('#notes');
	$.post('ajaxjs.php'),{postdescriptionO:descriptionO,postPurchaseO:PurchaseO,posttotal:total,postnotes:notes},

	$.ajax({
	type:'Post',
	url: 'index.php',
	data: $(this).serialize(),
	cache: false,
	success: function(result){
		$("display").html(result);

$descriptionO=$_POST['descriptionO'];
$PurchaseO=$_POST['PurchaseO'];
$total=$_POST['total'];
$notes=$_POST['notes'];