Tryit Editor v2.3

PHP Source:

<!DOCTYPE html>
<html>
<head>
<script>
function showUser(str) {
if (str=="") {
document.getElementById("txtHint").innerHTML="";
    return;
}
if (window.XMLHttpRequest) {
    // code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
} else { // code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function() {
if (xmlhttp.readyState==4 && xmlhttp.status==200) {
    document.getElementById("txtHint").innerHTML=xmlhttp.responseText;
    }
}
xmlhttp.open("GET","getuser.php?q="+str,true);
xmlhttp.send();
}