POPUP calendar in ASP.net

Question

so what I'm trying to do is to make a popup calendar by textbox by using datepicker. the problem that I faced is the calendar doesn't popup at all .

below is my code:

<link rel="stylesheet" href="//code.jquery.com/ui/1.12.1/themes/base/jquery-ui.css">
  <link rel="stylesheet" href="/resources/demos/style.css">
  <script src="http://code.jquery.com/ui/1.10.1/jquery-ui.js"></script>
  <script src="https://code.jquery.com/jquery-1.12.4.js"></script>

        <script  type ="text/javascript" >
            //   <script type="text/javascript" language="javascript">
            $(function () {
                //initialise the datepicker with the date format specified
                $(".datepicker").datepicker();

        </script>

next:

 <input id="txtSche1" type="text"  CssClass="datepicker" readonly="readonly"/>

Answer 1

so I try other method but but this time I'm using image button and it worked

   $(function () {
        $("[id$=txtSche1]").datepicker({
            showOn: 'button',
            buttonImageOnly: true,
            buttonImage: '../images/PopUpSmallCalendar.gif',

        });
    });

I also remove the class from the text input

<input id="txtSche1" type="text" readonly="readonly"/>