using jquery to sum the text box value in the child repeater control and show the total in the label in footer
<p>I am trying this code for in jquery to sum the text box value in the child repeater control and show the total in the label in footer. I get <code>null is null or not an object</code> error.</p>

<pre><code>function display(objSecName) {
    var objsec = objSecName;
    // var lablTotAmount = document.getElementById(objSecName);
    alert(objsec);
    $('.totamt input[type=text]').each(function () {
        $(this).change(function () {
            alert(calsum());
        });
    });

    function calsum() {
        var Total = 0;
        var limtamt = 120000;

        $('.totamt input[type=text]').each(function () {
            if (!isNaN(this.value) &amp;&amp; this.value.length != 0) {
                Total += parseFloat($(this).val());
                document.getElementById(lblTotalAmountId80C).value = Total;
            }
        });
        return Total;
    };
}
</code></pre>
