URL - Web APIs 编辑

The URL interface is used to parse, construct, normalize, and encode URLs. It works by providing properties which allow you to easily read and modify the components of a URL. You normally create a new URL object by specifying the URL as a string when calling its constructor, or by providing a relative URL and a base URL. You can then easily read the parsed components of the URL or make changes to the URL.

If a browser doesn't yet support the URL() constructor, you can access a URL object using the Window interface's Window.URL property. Be sure to check to see if any of your target browsers require this to be prefixed.

Note:

Constructor

new URL()

Creates and returns a URL object referencing the URL specified using an absolute URL string, or a relative URL string and a base URL string.

Properties

hash

A USVString containing a '#' followed by the fragment identifier of the URL.

host

A USVString containing the domain (that is the hostname) followed by (if a port was specified) a ':' and the port of the URL.

hostname

A USVString containing the domain of the URL.

href

A stringifier that returns a USVString containing the whole URL.

origin Read only

Returns a USVString containing the origin of the URL, that is its scheme, its domain and its port.

password

A USVString containing the password specified before the domain name.

pathname

Is a USVString containing an initial '/' followed by the path of the URL, not including the query string or fragment.

port

A USVString containing the port number of the URL.

protocol

A USVString containing the protocol scheme of the URL, including the final ':'.

search

A USVString indicating the URL's parameter string; if any parameters are provided, this string includes all of them, beginning with the leading ? character.

searchParams Read only

A URLSearchParams object which can be used to access the individual query parameters found in search.

username

A USVString containing the username specified before the domain name.

Methods

toString()

Returns a USVString containing the whole URL. It is a synonym for URL.href, though it can't be used to modify the value.

toJSON()

Returns a USVString containing the whole URL. It returns the same string as the href property.

Static methods

createObjectURL()

Returns a DOMString containing a unique blob URL, that is a URL with blob: as its scheme, followed by an opaque string uniquely identifying the object in the browser.

revokeObjectURL()

Revokes an object URL previously created using URL.createObjectURL().

Usage notes

The constructor takes a url parameter, and an optional base parameter to use as a base if the url parameter is a relative URL:

const url = new URL('../cats', 'http://www.example.com/dogs');
console.log(url.hostname); // "www.example.com"
console.log(url.pathname); // "/cats"

URL properties can be set to construct the URL:

url.hash = 'tabby';
console.log(url.href); // "http://www.example.com/cats#tabby"

URLs are encoded according to the rules found in RFC 3986. For instance:

url.pathname = 'démonstration.html';
console.log(url.href); // "http://www.example.com/d%C3%A9monstration.html"

The URLSearchParams interface can be used to build and manipulate the URL query string.

To get the search params from the current window's URL, you can do this:

// https://some.site/?id=123
const parsedUrl = new URL(window.location.href);
console.log(parsedUrl.searchParams.get("id")); // "123"

The toString() method of URL just returns the value of the href property, so the constructor can be used to normalize and encode a URL directly.

const response = await fetch(new URL('http://www.example.com/démonstration.html'));

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• URL API
• What is a URL?
• Property to obtain a URL object: Window.URL.
• URLSearchParams.