怎么样?

'https://stackoverflow.com/questions/736513/how-do-i-parse-a-url-into-hostname-and-path-in-javascript'.split('//').pop() .split('/')[0]

结果:

“stackoverflow.com”

var getLocation = function(href) {
    var l = document.createElement("a");
    l.href = href;
    return l;
};
var l = getLocation("http://example.com/path");
console.debug(l.hostname)
>> "example.com"
console.debug(l.pathname)
>> "/path"

function parseUrl(url) {
    var m = url.match(/^((?:([^:\/?#]+:)(?:\/\/))?((?:([^\/?#:]*):([^\/?#:]*)@)?([^\/?#:]*)(?::([^\/?#:]*))?))?([^?#]*)(\?[^#]*)?(#.*)?$/),
        r = {
            hash: m[10] || "",                   // #asd
            host: m[3] || "",                    // localhost:257
            hostname: m[6] || "",                // localhost
            href: m[0] || "",                    // http://username:password@localhost:257/deploy/?asd=asd#asd
            origin: m[1] || "",                  // http://username:password@localhost:257
            pathname: m[8] || (m[1] ? "/" : ""), // /deploy/
            port: m[7] || "",                    // 257
            protocol: m[2] || "",                // http:
            search: m[9] || "",                  // ?asd=asd
            username: m[4] || "",                // username
            password: m[5] || ""                 // password
        };
    if (r.protocol.length == 2) {
        r.protocol = "file:///" + r.protocol.toUpperCase();
        r.origin = r.protocol + "//" + r.host;
    }
    r.href = r.origin + r.pathname + r.search + r.hash;
    return r;
};
parseUrl("http://username:password@localhost:257/deploy/?asd=asd#asd");

它既适用于绝对url，也适用于相对url

js-uri(在谷歌Code上可用)接受字符串URL并从中解析URI对象:

var some_uri = new URI("http://www.example.com/foo/bar");

alert(some_uri.authority); // www.example.com
alert(some_uri);           // http://www.example.com/foo/bar

var blah      = new URI("blah");
var blah_full = blah.resolve(some_uri);
alert(blah_full);         // http://www.example.com/foo/blah

别再白费力气了。使用https://github.com/medialize/URI.js/

var uri = new URI("http://example.org:80/foo/hello.html");
// get host
uri.host(); // returns string "example.org:80"
// set host
uri.host("example.org:80");

为什么不用呢?

        $scope.get_location=function(url_str){
        var parser = document.createElement('a');
        parser.href =url_str;//"http://example.com:3000/pathname/?search=test#hash";
        var info={
            protocol:parser.protocol,   
            hostname:parser.hostname, // => "example.com"
            port:parser.port,     // => "3000"
            pathname:parser.pathname, // => "/pathname/"
            search:parser.search,   // => "?search=test"
            hash:parser.hash,     // => "#hash"
            host:parser.host, // => "example.com:3000"      
        }
        return info;
    }
    alert( JSON.stringify( $scope.get_location("http://localhost:257/index.php/deploy/?asd=asd#asd"),null,4 ) );