undifined variable

hi, i am new coldfusion programmer
i have 2 pages
in the first page we choose a conference room and we click on a submit for viewing the shcedule of this room in the second page where date=#searchdate#

<cfparam name="searchdate" default="#now()#">

<center> <h2><span class="textbox">#dateformat(searchdate,'dddd d mmmm yyyy')#</span>
</h2></center>
<cfset nextday = dateadd("d", 1, #searchdate#)>
<cfset prevday = dateadd("d", -1, #searchdate#)>
<cfset nextday=#dateformat(nextday, 'mm/dd/yyyy')#>
<cfset prevday=#dateformat(prevday, 'mm/dd/yyyy')#>

<table width="97%" height="21">
<tr>

<td width="37%" align="right" ><img name="btnprev" src="images/previmage.gif" align="absmiddle" alt="Previous Day" onClick="changedate('#prevday#')" > Go to day before</td>
<td width="22%" align="center" ><a href="roomschedule.cfm">Go to today</a></td>
<td width="41%" align="left" >Go to day after <img name="btnnext" src="images/nextimage.gif" align="absmiddle" alt="Next Day" onClick="changedate('#nextday#')"></td>

</tr>
</table>


/////////////////////////
this is the function changedate()


function changedate(a)
{
var id ;
var id = a;
var page = "roomschedule.cfm?";
page =page + 'searchdate=' + id;
window.location=(page);
}



when i click on nextday the error occured Variable ROOM is undefined, because room is comming from the first page.
i tried to use "input type=hidden" but there is no submit buttom.

i will be thankfull for u
Maya

If I understand correctly, and you have received ROOM from the previous page, then you can just add it as another parameter in your url as a part of your javascript function. Below should work if ROOM was sent as part of the url, if ROOM was sent as part of a form submit from your first page, then use #form.room# instead of #url.room#.

For url strings, use ampersands to connect multiple variables, I put that in the page update line. Also, you will need to be sure that it is enclosed in <cfoutput> tags so that the #signs get evaluated HTH

<cfoutput>
function changedate(a)
{
var id ;
var id = a;
var page = "roomschedule.cfm?room=#url.room#";
page =page + '&searchdate=' + id;
window.location=(page);
}
</cfoutput>

thank you very much it's working...