function getRef(obj){
        return (typeof obj == "string") ?
        document.getElementById(obj) : obj;
}
function setStyle(obj,style,value){
        getRef(obj).style[style]= value;
}
function setClassName(obj, className){
        getRef(obj).className= className;
}
function toggleStyle(obj, style, value1, value2){
        obj= getRef(obj);
        // obj.isValue1 will be false the first time.
        if(!obj.isValue1){
                obj.style[style]= value1;
                obj.isValue1= true;
        }
        else{
                obj.style[style]= value2;
                obj.isValue1= false;
        }
}
function toggleClassName(obj, class1, class2){
        obj= getRef(obj);
        // obj.isClass1 will be false the first time.
        if(!obj.isClass1){
                obj.className= class1;
                obj.isClass1= true;
        }
        else{
                obj.className= class2;
                obj.isClass1= false;
        }
}