function hostname(url) {
    var match = url.match(/:\/\/(www[0-9]?\.)?(.[^/:]+)/i);
    if ( match != null && match.length > 2 && typeof match[2] === 'string' && match[2].length > 0 ) return match[2];
}

上面的代码将成功解析以下示例url的主机名: http://WWW.first.com/folder/page.html first.com http://mail.google.com/folder/page.html mail.google.com https://mail.google.com/folder/page.html mail.google.com http://www2.somewhere.com/folder/page.html?q=1 somewhere.com https://www.another.eu/folder/page.html?q=1 another.eu

原文出处:http://www.primaryobjects.com/CMS/Article145

String.prototype.trim = function(){return his.replace(/^\s+|\s+$/g,"");}
function getHost(url){
    if("undefined"==typeof(url)||null==url) return "";
    url = url.trim(); if(""==url) return "";
    var _host,_arr;
    if(-1<url.indexOf("://")){
        _arr = url.split('://');
        if(-1<_arr[0].indexOf("/")||-1<_arr[0].indexOf(".")||-1<_arr[0].indexOf("\?")||-1<_arr[0].indexOf("\&")){
            _arr[0] = _arr[0].trim();
            if(0==_arr[0].indexOf("//")) _host = _arr[0].split("//")[1].split("/")[0].trim().split("\?")[0].split("\&")[0];
            else return "";
        }
        else{
            _arr[1] = _arr[1].trim();
            _host = _arr[1].split("/")[0].trim().split("\?")[0].split("\&")[0];
        }
    }
    else{
        if(0==url.indexOf("//")) _host = url.split("//")[1].split("/")[0].trim().split("\?")[0].split("\&")[0];
        else return "";
    }
    return _host;
}
function getHostname(url){
    if("undefined"==typeof(url)||null==url) return "";
    url = url.trim(); if(""==url) return "";
    return getHost(url).split(':')[0];
}
function getDomain(url){
    if("undefined"==typeof(url)||null==url) return "";
    url = url.trim(); if(""==url) return "";
    return getHostname(url).replace(/([a-zA-Z0-9]+.)/,"");
}

代码:

var regex = /\w+.(com|co\.kr|be)/ig;
var urls = ['http://www.youtube.com/watch?v=ClkQA2Lb_iE',
            'http://youtu.be/ClkQA2Lb_iE',
            'http://www.example.com/12xy45',
            'http://example.com/random'];


$.each(urls, function(index, url) {
    var convertedUrl = url.match(regex);
    console.log(convertedUrl);
});

结果:

youtube.com
youtu.be
example.com
example.com

简单来说，你可以这样做

var url = "http://www.someurl.com/support/feature"

function getDomain(url){
  domain=url.split("//")[1];
  return domain.split("/")[0];
}
eg:
  getDomain("http://www.example.com/page/1")

  output:
   "www.example.com"

使用上述函数获取域名

jquery Oneline

$('<a>').attr('href', document.location.href).prop('hostname');

所有url属性，没有依赖，没有JQuery，容易理解

这个解决方案给了你的答案和额外的性质。不需要JQuery或其他依赖，粘贴和走。

使用

getUrlParts("https://news.google.com/news/headlines/technology.html?ned=us&hl=en")

输出

{
  "origin": "https://news.google.com",
  "domain": "news.google.com",
  "subdomain": "news",
  "domainroot": "google.com",
  "domainpath": "news.google.com/news/headlines",
  "tld": ".com",
  "path": "news/headlines/technology.html",
  "query": "ned=us&hl=en",
  "protocol": "https",
  "port": 443,
  "parts": [
    "news",
    "google",
    "com"
  ],
  "segments": [
    "news",
    "headlines",
    "technology.html"
  ],
  "params": [
    {
      "key": "ned",
      "val": "us"
    },
    {
      "key": "hl",
      "val": "en"
    }
  ]
}

代码 代码设计得很容易理解，而不是超级快。每秒可以轻松调用100次，因此它非常适合前端或少量服务器使用，但不适用于高容量吞吐量。

function getUrlParts(fullyQualifiedUrl) {
    var url = {},
        tempProtocol
    var a = document.createElement('a')
    // if doesn't start with something like https:// it's not a url, but try to work around that
    if (fullyQualifiedUrl.indexOf('://') == -1) {
        tempProtocol = 'https://'
        a.href = tempProtocol + fullyQualifiedUrl
    } else
        a.href = fullyQualifiedUrl
    var parts = a.hostname.split('.')
    url.origin = tempProtocol ? "" : a.origin
    url.domain = a.hostname
    url.subdomain = parts[0]
    url.domainroot = ''
    url.domainpath = ''
    url.tld = '.' + parts[parts.length - 1]
    url.path = a.pathname.substring(1)
    url.query = a.search.substr(1)
    url.protocol = tempProtocol ? "" : a.protocol.substr(0, a.protocol.length - 1)
    url.port = tempProtocol ? "" : a.port ? a.port : a.protocol === 'http:' ? 80 : a.protocol === 'https:' ? 443 : a.port
    url.parts = parts
    url.segments = a.pathname === '/' ? [] : a.pathname.split('/').slice(1)
    url.params = url.query === '' ? [] : url.query.split('&')
    for (var j = 0; j < url.params.length; j++) {
        var param = url.params[j];
        var keyval = param.split('=')
        url.params[j] = {
            'key': keyval[0],
            'val': keyval[1]
        }
    }
    // domainroot
    if (parts.length > 2) {
        url.domainroot = parts[parts.length - 2] + '.' + parts[parts.length - 1];
        // check for country code top level domain
        if (parts[parts.length - 1].length == 2 && parts[parts.length - 1].length == 2)
            url.domainroot = parts[parts.length - 3] + '.' + url.domainroot;
    }
    // domainpath (domain+path without filenames) 
    if (url.segments.length > 0) {
        var lastSegment = url.segments[url.segments.length - 1]
        var endsWithFile = lastSegment.indexOf('.') != -1
        if (endsWithFile) {
            var fileSegment = url.path.indexOf(lastSegment)
            var pathNoFile = url.path.substr(0, fileSegment - 1)
            url.domainpath = url.domain
            if (pathNoFile)
                url.domainpath = url.domainpath + '/' + pathNoFile
        } else
            url.domainpath = url.domain + '/' + url.path
    } else
        url.domainpath = url.domain
    return url
}