var XMLHttpRequest = XMLHttpRequest || window.ActiveXObject && function () {
    return new ActiveXObject('Msxml2.XMLHTTP');
};

function get_s(url) {
    var xhr = new XMLHttpRequest();
    xhr.open('get', url, false);
    xhr.send(null);
    return xhr.responseText;
}


window.onload = function () {
    var link = document.getElementById('historyAPI');
    link.addEventListener("click",
            function (e) {
                e.preventDefault();
                getContent(link, true);
            }, true
            );
};

window.addEventListener("popstate", function (e) {
    getContent(location.pathname, false);
});



function getContent(link, addEntry)
{
    var url = link.href.replace(/^.*?:\/\/.*?(?=\/|$)/, '');
    var result = get_s(url);
    contentHolder.innerHTML = result;
    if (addEntry === true) {
        history.pushState(null, null, link.href);
    }
}