Chrome扩展程序可检查断开的链接检测器

Question

我创建了一个chrome插件，该插件可以检测锚点检测器，并将锚点背景突出显示为红色。对于某些链接，即使它存在于同一域或外部链接中也显示为CORS错误。

请找到以下代码。

document.getElementById("test").addEventListener('click', () => {
    console.log("Popup DOM fully loaded and parsed");


function CheckLinks(lnks) {
Object.keys(lnks).map(function(key) {
  return [lnks[key].href, lnks[key].parentElement];
}).map((a) => {
if(a[0].indexOf('javascript') === -1 && a[0].indexOf('mailto') === -1){
UrlExists(a[0], 'GET', '', (exists) => {
if(!exists){
 a[1].style.background = "Red";
}
}, (errorText) => {
 console.log(errorText);
});
}
});

}

    function modifyDOM() {

    function UrlExists(url, method, data, callback, errback) {
    var req;

    if(XMLHttpRequest) {
        req = new XMLHttpRequest();

        if('withCredentials' in req) {
            req.open(method, url, true);
            req.onerror = errback;
            req.onreadystatechange = function() {
                if (req.readyState === 4) {
                    if (req.status >= 200 && req.status < 400) {
                        callback(true);
                    } else {
                        callback(false);
                    }
                }
            };
        req.setRequestHeader("Access-Control-Allow-Origin",true);
            req.send(data);
        }
    } else if(XDomainRequest) {
        req = new XDomainRequest();
        req.open(method, url);
        req.onerror = errback;
        req.onload = function() {
            callback(true);
        };
        req.send(data);
    } else {
        errback('CORS not supported');
    }
  }

        //You can play with your DOM here or check URL against your regex
        console.log('Tab script:');
        console.log(document.links);
        Object.keys(document.links).map(function(key) {
  return [document.links[key].href, document.links[key].parentElement];
}).map((a) => {
if(a[0].indexOf('javascript') === -1){
UrlExists(a[0], 'GET', '', (exists) => {
if(!exists){
 a[1].style.background = "Red";
}
}, (errorText) => {
 console.log(errorText);
});
}
});


    }



    //We have permission to access the activeTab, so we can call chrome.tabs.executeScript:
    chrome.tabs.executeScript({
        code: '(' + modifyDOM + ')();' //argument here is a string but function.toString() returns function's code
    }, (results) => {
        //Here we have just the innerHTML and not DOM structure
        console.log('Popup script:')
        console.log(results[0]);
    //CheckLinks(results[0]);
    });
});

一些错误

  

对预检请求的响应未通过访问控制检查：否   请求中存在“ Access-Control-Allow-Origin”标头   资源。

     

无法加载https://portal.office.com/account/#security：响应   飞行前检查无效（重定向）