What is an URL?
A URL, or Uniform Resource Locator, refers to a web address. For example, a text-based URL could be logic-practice.com. Alternatively, a URL can be constructed using an IP address, such as 192.168.2.24. Typically, users prefer to input the name's address during an internet search since names are generally simpler to recall compared to numerical values.
Web browsers utilize URLs to request specific pages from web servers. The following is a breakdown of the syntax and structure of a URL.
Syntax
Scheme://prefix.domain:port/path/filename
Parameters
Scheme-
The category of Internet service is defined, with a general emphasis on the use of either http or https.
Prefix-
It sets a domain prefix, with "www" being the standard for HTTP.
Domain-
It addresses the concept of a domain name within the online sphere (for instance, logic-practice.com).
Port -
It determines the port on the host, with 80 being the standard port for HTTP.
Path -
It creates a path on the server side.
Filename -
It identifies a resource's or document's name.
Retrieving the domain name from a URL using JavaScript can serve multiple purposes, including web analytics and security considerations. In this discussion, we will examine various methods to obtain the domain name from a URL in JavaScript, highlighting the advantages and disadvantages of each approach.
1. Using the window.location object
The simplest method to extract the domain name from a URL in JavaScript is by utilizing the window.location object, which contains details regarding the active URL. The window.location.host property yields the domain name, inclusive of the port number if it exists. Below is an illustration:
Const domain = window.location.host;
This method offers the benefit of being straightforward and dependable. Nonetheless, it is limited to functioning with the present URL; therefore, if your intention is to retrieve the domain name from an alternate URL, you will have to employ a different technique.
2. Using the URL constructor
An alternative method for obtaining the domain name from a URL in JavaScript is by utilizing the URL constructor. This is a native JavaScript object designed to parse a URL string and grant access to its different elements. Below is an illustration:
Consturl = new URL("https://logic-practice.com/path/to/file.html");
Const domain = url.hostname;
The URL constructor offers the benefit of being capable of retrieving the domain name from any legitimate URL, rather than being limited to just the current one. Nevertheless, it is only supported in contemporary web browsers, which means it is essential to verify its compatibility prior to implementation.
3. Using regular expressions
A more sophisticated method for retrieving the domain name from a URL in JavaScript involves the utilization of regular expressions. Regular expressions serve as a robust mechanism for identifying patterns, allowing us to effectively extract the domain name from a given URL. Below is an illustrative example:
Consturl = "https://logic-practice.com/path/to/file.html";
Constdomain = url.match(/^(?:https?:\/\/)?(?:[^@\n]+@)?(?:www\.)?([^:\/\n]+)/im)[1];
This regex pattern identifies the domain name within a URL while disregarding the protocol (either http or https), any username and password credentials, and the path. It operates by searching for the initial instance of a string of characters that excludes a colon, a slash, or a newline, which may be preceded by an optional protocol, username and password, as well as a potential "www." prefix. The match method yields an array that consists of the complete match alongside any captured groups; therefore, we need to retrieve the second element (located at index 1) to obtain the domain name.
This method offers the benefit of being versatile and capable of adjusting to various URL structures; however, it is also more intricate and susceptible to mistakes if the regular expression pattern lacks sufficient accuracy.
4. Using the DOM
Ultimately, we can also retrieve the domain name from a URL in JavaScript by leveraging the Document Object Model (DOM). To achieve this, we can create a concealed anchor element, assign its href attribute to the URL from which we wish to extract the domain name, and subsequently access the hostname property. Below is an illustration:
Consturl = "https://logic-practice.com/path/to/file.html";
Const a = document.createelement("a");
A.href = url;
Const domain = a.hostname;
This method is straightforward to comprehend and execute; however, it also generates a DOM element, which could lead to performance issues if this action is performed frequently.
Conclusion
In JavaScript, there are several techniques to retrieve the domain name from a URL, and the most suitable method will depend on your specific needs and limitations. If your goal is solely to obtain the domain name from the active URL, utilizing the window.location object stands out as the easiest and most dependable approach.