实时更新在线人数和累计观看人数

<h6><center><p>当前在线：<span id='slzxrs'><?php echo slzxrs(); ?></span> 人_ 累计观看人数：<span id='sxcs'><?php echo sxcs(); ?></span> 人</p></center></h6>
<script>
setInterval(function(){
    var xmlhttp = new XMLHttpRequest();
    xmlhttp.onreadystatechange = function() {
        if (this.readyState === 4 && this.status === 200) {
            document.getElementById('slzxrs').innerHTML = this.responseText;
        }
    };
    xmlhttp.open('GET', 'slzxrs.php', true);
    xmlhttp.send();

    var xmlhttp2 = new XMLHttpRequest();
    xmlhttp2.onreadystatechange = function() {
        if (this.readyState === 4 && this.status === 200) {
            document.getElementById('sxcs').innerHTML = this.responseText;
        }
    };
    xmlhttp2.open('GET', 'sxcs.php', true);
    xmlhttp2.send();
}, 1000); // 1000毫秒 = 1秒
</script>