onmouseover跟onmouseout应用于RadioButtonList或CheckBoxList

onmouseover和onmouseout应用于RadioButtonList或CheckBoxList
<script type="text/javascript">
        function windowOnLoad() {
            var rbl = document.getElementById('<%= RadioButtonListFivePhases.ClientID %>');
            var labels = rbl.getElementsByTagName('label');

            for (var i = 0; i < labels.length; i++) {
                var lbl = labels[i];

                lbl.onmouseover = function () {
                    this.className = 'overStyle';
                };

                lbl.onmouseout = function () {
                    this.className = 'outStyle';
                };
            }
        }
        window.onload = windowOnLoad;
    </script>
<style type="text/css">
        .overStyle {
            font-weight: bold;
            color: #f00;
        }

        .outStyle {
            font-weight: normal;
            color: none;
        }
    </style>