How to set session based Hide/show message notice?

[toplisek]

I have set Javascript function to Expand or Collapse my messages.

PHP Code:



<div onclick="javascript:js_message.expcollap();" style="">&nbsp;</div>

<button id="show">Show</button>


<script language="JavaScript" type="text/javascript">
/*<![CDATA[*/
var js_message = {expcollap:function () {$("#message_notice").click(function(){$("div").hide(1000);});$("#show").click(function(){$("div").show();});
}}
/*]]>*/
</script> 


How to set session value that user will see this message only once even he visits page twice (back button or click on the same URL).