function doSearch()
{
    var text = document.getElementById("txtSearchQuery");
    if(text.value == "")
    {
        document.getElementById("announcementMessage").innerHTML = "You must enter some search keywords.";
        $(".announcement").slideDown("slow");
    }
    else
    {
        window.location = "SearchResults.aspx?SearchExpression=" + text.value;
    }
}