JavaScript replace() Method: Replace String Values

The JavaScript 'replace()' method is used to replace a specified value or regular expression with a new value. It returns a new string with the replaced value.

Syntax:

string.replace(searchValue, newValue)

Parameters:

• 'searchValue': The value or regular expression to be replaced.
• 'newValue': The new value to replace the 'searchValue' with.

Example 1: Replacing a single occurrence of a value

let str = 'Hello World';
let newStr = str.replace('World', 'JavaScript');
console.log(newStr); // Output: Hello JavaScript

Example 2: Replacing all occurrences of a value using a regular expression with the 'g' flag

let str = 'Hello World, World';
let newStr = str.replace(/World/g, 'JavaScript');
console.log(newStr); // Output: Hello JavaScript, JavaScript

Note: By default, the 'replace()' method only replaces the first occurrence of the 'searchValue'. To replace all occurrences, use a regular expression with the 'g' (global) flag.