var Core = {};

Core.getElementsByClass = function(theClass) {
    var elementArray = [];
    if (document.all)
    {
    elementArray = document.all;
    }
    else
    {
    elementArray = document.getElementsByTagName("*");
    }
    var matchedArray = [];
    var pattern = new RegExp("(^| )" + theClass + "( |$)");
    for (var i = 0; i < elementArray.length; i++)
    {
    if (pattern.test(elementArray[i].className))
    {
      matchedArray[matchedArray.length] = elementArray[i];
    }
    }
    return matchedArray;
};

function hideClass(classObj) {
    var list = Core.getElementsByClass(classObj);
    for (var i = 0; i < list.length; i++) {
    list[i].style.display = 'none';
    }
}

function showDiv(divObj) {
    document.getElementById(divObj).style.display='block';
}

function hideDiv(divObj) {
    document.getElementById(divObj).style.display='none';
}

function revertClass(classObj) {
    var list = Core.getElementsByClass(classObj);
    for (var i = 0; i < list.length; i++) {
    list[i].className = classObj;
    }
}