Getting value of selected checkboxlist items.

<script type = "text/javascript">
function Get_CheckBoxList_Values(chk)
{
    var chkBox = document.getElementById('<%= chk_project.ClientID %>');
    var options = chkBox.getElementsByTagName('input');
    var listOfSpans = chkBox.getElementsByTagName('span');

    for (var i = 0; i<= options.length-1; i++)
    {
        if(options[i].checked)
        {
            alert(listOfSpans[i].attributes["JSvalue"].value);
        }
    }
}
</script>