var http = location.protocol;
var slashes = http.concat("//");
var host = slashes.concat(window.location.hostname);

出于某种原因，所有的答案都是多余的。这就是一切:

window.location.origin

更多细节可以在这里找到:https://developer.mozilla.org/en-US/docs/Web/API/window.location#Properties

var getBasePath = function(url) {
    var r = ('' + url).match(/^(https?:)?\/\/[^/]+/i);
    return r ? r[0] : '';
};

适用于所有浏览器的简单答案:

let origin;

if (!window.location.origin) {
  origin = window.location.protocol + "//" + window.location.hostname + 
     (window.location.port ? ':' + window.location.port: '');
}

origin = window.location.origin;

console.log(`${req.protocol}://${req.get('host')}/${req.originalUrl}`);

要求的事情。protocol -给出你使用的协议(例如HTTP) get(host) -给出带有端口号的主机名(例如localhost:8080)

var http = location.protocol;
var slashes = http.concat("//");
var host = slashes.concat(window.location.hostname);