function ajax(url)
{req = null;if (window.XMLHttpRequest) {
req = new XMLHttpRequest();req.onreadystatechange = processReqChange;
req.open("GET",url,true);req.send(null);} else if (window.ActiveXObject) 
{
req = new ActiveXObject("Microsoft.XMLHTTP");
if (req) {
req.onreadystatechange = processReqChange;req.open("GET",url,true);
req.send();
}
}
}
function processReqChange(){if (req.readyState == 1) {
document.getElementById("caixa_textos").innerHTML = 'Carregando, por favor aguarde...';
}
else if (req.readyState == 4) {if (req.status ==200) {
document.getElementById("caixa_textos").innerHTML = req.responseText;} else {
alert("Houve um problema ao obter os dados:n" + req.statusText);
}
}
}