searching through an array

i want to search an array and return one set of data if the keyword is in the array and a different set of data if it is not. i have an idea of how to do this, but it doesn't seem to be working... any suggestions or help would be greatly appreciated.

Hi:
You can see this code:
<script language="JavaScript">
var arreglo = new Array(10);
function search(arreglo,element)
{
var i = 0 ;
var flag = true ;

while (i<10 && flag)
{
if (arreglo[i]==element)
flag = false;
else
i++;
}
if (flag)//element dont searched
return false;
else
return true;
}