How to Extract URLs from a String in JavaScript ?

In this article, we are given a string str which consists of a hyperlink or URL present in it. We need to extract the URL from the string using JavaScript. The URL must be complete and you need to print the entire URL.

Example:

Input :-
str = "Platform for geeks: https://www.geeksforgeeks.org/"
Output :-
https://www.geeksforgeeks.org/
Explanation: 
In the input string "https://www.geeksforgeeks.org//" is a URL and we are required to extract this URL.

Approaches to extract URLs from a string in JavaScript:

Approach 1: Using Regular Expressions

In this approach, we use the match method to find the first occurrence of a URL in the string. The regular expression `/https?:\/\/[^\s]+/` matches any string that starts with http or https, followed by one or more non-space characters. The [0] at the end of the match method returns the first match which is the entire URL present in the string.

Example: Below is the implementation of this approach

let str = "Platform for geeks: https://www.geeksforgeeks.org/";
let res = str.match(/https?:\/\/[^\s]+/)[0];
console.log("The extracted URL from given string is:- " + res);

The extracted URL from given string is:- https://www.geeksforgeeks.org/

Approach 2: Using the split() Method

In this approach, we use the split() method to split the string into an array of words and then we use the find method to find the first word that starts with http or https. This approach assumes that the URL is separated from the rest of the string by whitespaces meaning that there shouldn't be any whitespaces in the URL .

Example: Below is the implementation of this approach

let str = "Platform for geeks: https://www.geeksforgeeks.org/";
let res = str.split(" ").find(word => word.startsWith("http"));
console.log("The extracted URL from given string is: " + res);

The extracted URL from given string is: https://www.geeksforgeeks.org/

Approach 3: Using the URL Constructor

In this approach, we iterate over each word in the string, attempt to create a URL object, and check if it is a valid URL. This method is more robust as it explicitly verifies the validity of the URL.

Example: Below is the implementation of this approach:

let str = "Platform for geeks https://www.geeksforgeeks.org/";
let words = str.split(/\s+/); // Using a regex to split by whitespace
let url = null; // Initialize url to null

for (let word of words) {
    try {
        let potentialUrl = new URL(word);
        url = potentialUrl.href;
        break;
    } catch (e) {
        // If the word is not a valid URL, it will throw an error which we ignore
    }
}

if (url !== null) {
    console.log("The extracted URL from given string is: " + url);
} else {
    console.log("No URL found in the given string.");
}

The extracted URL from given string is: https://www.geeksforgeeks.org//