var request;
var dest;
function processStateChange(){
if (request.readyState < 4) document.getElementById(dest).innerHTML = "Загрузка...";
if (request.readyState == 4){
contentDiv = document.getElementById(dest);
if (request.status == 200){



response = request.responseText ;
contentDiv.innerHTML = response;




} else {
contentDiv.innerHTML = "Error: Status "+request.status;
}

}
}


function test1( destination  ){
dest = destination;
URL = "test_print.php";
arg = "act=" + dest ;
if (window.XMLHttpRequest){
request = new XMLHttpRequest();
request.onreadystatechange = processStateChange;
request.open("POST", URL, true);
request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
request.send(arg);
} else if (window.ActiveXObject) {
request = new ActiveXObject("Microsoft.XMLHTTP");
if (request) {
request.onreadystatechange = processStateChange;
request.open("POST", URL, true);
request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
request.send(arg);
}
}
}


<div id="t1"> 1 </div>  

 <div id="t2"> 2 </div>   
<input type="button" onclick="test1('t1')" value="go">

<?print "1111"?>