function makeObject(){
       var x;
       if (window.ActiveXObject) {
          x = new ActiveXObject("Microsoft.XMLHTTP");
       }else if (window.XMLHttpRequest) {
          x = new XMLHttpRequest();
       }
       return x;
}

var request = makeObject();

var the_content;

function check_content(the_content){
       request.open('get', the_content);
       request.onreadystatechange = parseCheck_content;
       request.send('');
}

function parseCheck_content(){
       if(request.readyState == 1){
          document.getElementById('content').innerHTML = 'Chargement...';
       }
       if(request.readyState == 4){
          var answer = request.responseText;
          document.getElementById('content').innerHTML = answer;
       }
}