example-ajax.html

<html>

<script>

function mywatch() {

    var xmlhttp;
    xmlhttp=new XMLHttpRequest();
    // for the time being we are using webdis
    xmlhttp.open("GET","http://127.0.0.1:7379/GET/rfidcard.txt",true);
    xmlhttp.send();
    xmlhttp.onreadystatechange=function()
    {
	if (xmlhttp.readyState==4 && xmlhttp.status==200)
	{
	    document.getElementById("inputOperatore").value=xmlhttp.responseText;
	}
    }
}

</script>

<body onLoad="setInterval('mywatch();',500);">

<input type="text" id="inputOperatore" size=50>

</body>
</html>