In this article I will show you how to focus() button using JQuery example. In this coding is used to focus the first input button. For this option you should give input[type=button] . Then put the jQuery focus() property.

JQuery Code:

<script src="Scripts/jquery-1.7.1.min.js"></script>
    <script type="text/javascript">
        $('document').ready(function() {
            $("input[type=button]:first").focus();
            $("#button").click(function () {

                var a = parseFloat($("#a").val());
                var b = parseFloat($("#b").val());
                var c = a / b;
                $("#result").val(c);
            });
        });
   </script>
<div style="padding-bottom: 5px">
        Enter the  number a
        <input type="text" id="a" value="5" />
    </div> 

    <div style="padding-bottom: 15px">
        Enter the  number b<input type="text" id="b" value="15" />
    </div>
    <input type="button" value="Division" id="button" />
    <br />
    Result
    <input type="text" id="result" />