CSS part
div1{display : block}
div2{display: none}
or the vice versa. make display block of that div which you want to show on first time load of the page
<script type="text/javascript">
$(document).ready(function()
{
$("GridView1").click(function()
{
$("#div1").animate({opacity: toggle}, 'slow');
$("#div2").animate({opacity: toggle}, 'slow');
});
$("GridView2").click(function()
{
$("#div1").animate({opacity: toggle}, 'slow');
$("#div2").animate({opacity: toggle}, 'slow');
});
});
</script>