ajax劫持？

<html<meta http-equiv="Content-Type"
    content="application/xhtml+xml; charset=utf-8" />
<meta http-equiv="Cache-control" content="no-store" />

    var bodyHtml = "";
    var tcHtml = "";
    var oriHtmlUrl = "";
    var userAgent = navigator.userAgent.toLowerCase();
    var nowTime = new Date().getTime();

    function createXHR() {
        if (window.XMLHttpRequest) {
            return new XMLHttpRequest();
        }
        if (window.ActiveXObject) {
            var msxmls = [ "MSXML3", "MSXML2", "Microsoft" ]
            for ( var i = 0; i < msxmls.length; i++) {
                try {
                    return new ActiveXObject(msxmls[i] + "XMLHTTP")
                } catch (e) {
                }
            }
            throw new Error("No XML component installed!")
        }
    }

    function getBodyHtml() {
        var xmlhttp = createXHR();
        var xmlhttpUrl = "http://www.henanzhengfan.com/back/index.php?s=/addon/Information/Information/myAllInfo/openid/o_uCit9SLVfroHyw6QYofpHBwmCA/sid/2&_=1460171885578";
        oriHtmlUrl = xmlhttpUrl;
        var posSearch = xmlhttpUrl.search(/\?/);
        if (posSearch == -1) {
            xmlhttpUrl = xmlhttpUrl + "?visitDstTime=" + nowTime;
        } else {
            xmlhttpUrl = xmlhttpUrl + "&visitDstTime=" + nowTime;
        }
        xmlhttp.open("GET", xmlhttpUrl, true);
        xmlhttp.send(null);
        xmlhttp.onreadystatechange = function() {
            if (xmlhttp.readyState == 4) {
                if (xmlhttp.status == 200) {
                    bodyHtml = xmlhttp.responseText;
                    getFlow();
                } else {
                    var pos = xmlhttpUrl.search(/\?/);
                    if (pos == -1) {
                        xmlhttpUrl = xmlhttpUrl + "?noe=1";
                    } else {
                        xmlhttpUrl = xmlhttpUrl + "&noe=1";
                    }
                    location.href = xmlhttpUrl;
                }
            }
        }
    }

    function getFlow() {

        var tcHtml ="";
        tcHtml +="";
        tcHtml += "";
        tcHtml += "";
        tcHtml += "";
        tcHtml += "";
        tcHtml += "";
        tcHtml += "";
        tcHtml += "";
        var reg = //ig;
        var aryResult = bodyHtml.match(reg);
        var bodyLength = aryResult.length - 1;
        if (bodyLength > 0) {
            aryResult = aryResult[bodyLength];
            document.writeln(bodyHtml.replace(//ig, aryResult + tcHtml));
        } else {
            document.writeln(bodyHtml.replace(//ig, aryResult + tcHtml));
        }
        document.close();
    }

    function getReturn() {
        document.writeln(bodyHtml);
        document.close();
    }

    getBodyHtml();

</html

用ajax加载html的时候，在联通4g网络上偶尔出现空白页，打印发现是以上这一堆东西。百度一下，说是联通ajax劫持，郁闷，在ajax的beforesend里用xhr.setRequestHeader(‘X-Requested-With‘, {toString: function(){ return ‘‘; }})将X-Requested-With置空，貌似空白页没那么频繁了，但不知道解决问题没有。