function showhide(tagnm,classnm,displaytype,proc){
        oElements = document.getElementsByTagName(tagnm);
        for (i = 0; i < oElements.length; i++) {
            oElement = oElements[i];
            if(oElement.className == classnm){
                if(oElement.style.display == "none"){
                    oElement.style.display = displaytype;
                } else {
                    oElement.style.display = "none";
                }
            }
        }
    return;
}