Récuperer span

<div id="boite_onglets">
	<ul id="onglets">
		<li><a href="#" onclick="afficher_onglet('accueil'); return false;">Accueil</a>
		<li><a href="#" onclick="afficher_onglet('photos'); return false;">Photos</a>
	</ul>

	<div id="onglet_accueil">
		<h3>Accueil</h3>
		Contenu de l'onglet "Accueil"
	</div>

	<div id="onglet_photos" class="hidden">
		<h3>Photos</h3>
		Contenu de l'onglet "Photos"
	</div>
</div>

<script type="text/javascript">
var onglets;

window.onload = function() {
	var boite = document.getElementById('boite_onglets');
	onglets = boite.getElementsByTagName('div');
};

function afficher_onglet(id) {
	for(i = 0 ; i < onglets.length ; i++) {
		onglets[i].style.display = 'none';
	}

	document.getElementById('onglet_'+id).style.display = 'block';
}
</script>

<style type="text/css">
.hidden { display: none; }
</style>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Document sans nom</title>
</head>

<body>
<span class="bonj">Salut à tous</span> <span class="ok">aurevoir</span>
<SCRIPT language="Javascript">
<!--
	document.getElementsByTagName('bonj').innerHTML
	document.getElementsByTagName('ok).innerHTML 

// -->
</SCRIPT> 
</body>
</html>