Operations with Calendar attached to input

You can attach calendar to input object.

Arrival Date:

Stay for days

Departure Date:

Source

<link rel="STYLESHEET" type="text/css" href="../../codebase/dhtmlxcalendar.css">
<script>window.dhx_globalImgPath = "../../codebase/imgs/";</script>
<script  src="../../codebase/dhtmlxcommon.js"></script>
<script  src="../../codebase/dhtmlxcalendar.js"></script>
<script>var cal1;
window.onload = function() {
    cal1 = new dhtmlxCalendarObject('calInput1');
    cal1.attachEvent("onClick", function(date) {
        calDeptDate(date);
    });
}
function calDeptDate(date) {
    var d = new Date(date);
    d.setDate(d.getDate() + parseInt(document.getElementById("stay_days").value));
    document.getElementById("dept_date").innerHTML = d.getFullYear() + "-" + (d.getMonth() + 1) + "-" + d.getDate();
}</script>
 
 
<div>Arrival Date:</div>
<input type="text" id="calInput1" style="width: 200px; font-size:12px;" readonly="true">
<br>
<br>    
<div>Stay for 
<input type="text" id="stay_days" style="width: 40px; font-size:12px;" onblur="calDeptDate(cal1.getDate())" value="1"> days</div>
<br>
<div>Departure Date:</div>
<div id="dept_date"></div>
<br>