Creating the virtual keyboard numbers using ASP.Net and Javascript

Virtual keyboard for the numbers can be created by using HTML buttons and a piece of javascript code. I have used 11 buttons including backspace button and a textbox to display the text that have been entered. Please find the below code for the reference.


ASPX Page coding:   HTML and JAVAscript


<html>
<head id="Head1" runat="server">
 <title>Virtual Keyboard :fourthbottle</title>
  <script type="text/javascript">
   function input(e) {
       var txtinput = document.getElementById("txtinput");
       txtinput.value = txtinput.value + e.value;
       }

   function delet() {
       var txtinput = document.getElementById("txtinput");
       txtinput.value = txtinput.value.substr(0, txtinput.value.length - 1);
     }
    </script>
    <style type="text/css">
        .btn
        {
            background-color: Orange;
            color: Black;
            width: 20px;
            height: 20px;
        }
        .btnbck
        {
            background-color: Red;
            color: Black;
            width: 44px;
            height: 20px;
        }
    </style>
</head>
<body>
<form id="form1" runat="server">
<div>
<input id="txtinput" type="text" style="width: 150px" />
<p />
<div id="VirtualKey">
<input id="b1" type="button" value="1" class="btn" onclick="input(this);" />
<input id="b2" type="button" value="2" class="btn" onclick="input(this);" />
<input id="b3" type="button" value="3" class="btn" onclick="input(this);" />
  <br />
<input id="b4" type="button" value="4" class="btn" onclick="input(this);" />
<input id="b5" type="button" value="5" class="btn" onclick="input(this);" />
<input id="b6" type="button" value="6" class="btn" onclick="input(this);" />
 <br />
<input id="b7" type="button" value="7" class="btn" onclick="input(this);" />
<input id="b8" type="button" value="8" class="btn" onclick="input(this);" />
<input id="b9" type="button" value="9" class="btn" onclick="input(this);" />
 <br />
<input id="b0" type="button" value="0" class="btn" onclick="input(this)" />
<input id="bd" type="button" class="btnbck" value=" <<" onclick="delet();" />
 </div>
</div>
</form>
</body>
</html>