JS/jQuery Show DIV when page load and Hide when click

Question

I want to Show DIV when page is first time page load and when click the side bar menu I will disappear. My own code is whenever the menu is clicked(page reload) the DIV always appear and gone recently.

Sorry for my bad English :D

if (isset($_GET['ex'])) 
{
test();                         
<script>
    $("#hello").hide(1000);                 
</script>
}

Answer 1

Something like this:

<?php
if (isset($_GET['ex'])) {
test();
?>
<script>
$(function() {
    $("#hello").show();
    $("#sideBar").click(function() {
        $('#hello').hide(1000);
    });
});
</script>
<?php
    }
?>