js改变字体大小

    <form id="form1" runat="server">
    <a onclick="javascript:changefs('16');" style="cursor: pointer">大</a> <a onclick="javascript:changefs('14');"
        style="cursor: pointer">中</a> <a onclick="javascript:changefs('12');" style="cursor: pointer">
            小</a>
    <br />
    <div id="Icontent" runat="server">
        asdfasdfasdfasdfasdfasdfasdfasdfas
    </div>
    </form>
    <script type="text/javascript">
        function changefs(size) {
            document.getElementById('<%=Icontent.ClientID%>').style.fontSize = size + "px";
        }
    </script>