Call button on hit enter key in a text box

<script type="text/javascript">
    function ApplyFilterOnEnterKey(e) {
        if (e.keyCode == 13) {
            document.getElementById("_ctl0:mainContent:Search").click();
            return false;
        }
    }
</script>


Add the following attribute to the textbox:
onkeypress="return ApplyFilterOnEnterKey(event)"