function batchoperator() {
   setvisible("top_operate");
   setvisible("bottom_operate");

   return false;
}

function setvisible(id) {
    var div = document.getElementById(id);
    if (div) {
        if (div.style.display == "none")
            div.style.display = "block";
        else
            div.style.display = "none";
    }
}