How to usea Regular Expression in Javascript

Q: How to usea Regular Expression in Javascript

This approach defines a custom function toLowerCaseCustom that splits the string into an array of characters, maps over each character converting it to lowercase using toLowerCase(), and then joins the characters back into a string.

Approach 2: Using a Custom Function with map() and toLowerCase()

This approach utilizes a regular expression to match all uppercase letters in the string and replaces them with their lowercase equivalents using the replace() function.

Example: Here, a custom function toLowerCaseRegex is defined to convert the string to lowercase using a regular expression. The regular expression /[A-Z]/g matches all uppercase letters in the string. The replace() function is then used to replace each uppercase letter with its lowercase equivalent using a callback function (match => match.toLowerCase()). This function is called with the originalString variable, and the result is stored in lowercasedString, which is then logged to the console.

Javascript

function toLowerCaseRegex(string) {
  return string.replace(/[A-Z]/g, match => match.toLowerCase());
}
 
let originalString = "HeLLo WoRLD";
let lowercasedString = toLowerCaseRegex(originalString);
 
console.log(lowercasedString); // Output: "hello world"

Output

hello world

How to Lowercase a String in JavaScript ?

In JavaScript, converting a string to lowercase means transforming all the characters in the string to their lowercase equivalents. This operation is often used to ensure consistent comparison or formatting of text.

Below are the approaches used to Lowercase a string in JavaScript: