function hideDivOver () {
	var id = document.getElementById('over');
	id.style.display = 'none';
}

function displayDivOver() {
	var id = document.getElementById('over');
	id.style.display = 'block';
}

function hide(target) {
	var id = document.getElementById(target);
	
	hideDivOver();
	id.style.display = 'none';
}

function display(target) {
	var id = document.getElementById(target);
	
	displayDivOver();
	id.style.display = 'block';
}

function alertContents(httpRequest, where) {

	if (httpRequest.readyState == 4) {
		if (httpRequest.status == 200) {
			document.getElementById(where).innerHTML = httpRequest.responseText;
		} else {
			alert('Un problème est survenu avec la requête.');
		}
	}

}

function makeRequest(what, where) {

	var httpRequest = false;

	if (window.XMLHttpRequest) { // Mozilla, Safari,...
		httpRequest = new XMLHttpRequest();
		if (httpRequest.overrideMimeType) {
			httpRequest.overrideMimeType('text/xml');
		}
	} else if (window.ActiveXObject) { // IE
		try {
			httpRequest = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e) {
			try {
				httpRequest = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch (e) {}
		}
	}

	if (!httpRequest) {
		alert('Abandon :( Impossible de créer une instance XMLHTTP');
		return false;
	}
	httpRequest.onreadystatechange = function() { alertContents(httpRequest, where); };
	httpRequest.open('GET', what, true);
	httpRequest.send(null);

}