JavaScript Map set() Method (original) (raw)
Last Updated : 15 Jul, 2024
The JavaScript **map.set() method is used to add **key-value pairs to a Map object. It can also be used to update the value of an existing key. Each value must have a unique key so that they get mapped correctly.
**Syntax:
GFGmap.set(key, value);
**Parameters:
This method accepts two parameters as mentioned above and described below:
- **Key: This is the key of the item that has to be added or updated in the Map.
- **Value: This is the value of the item that has to be added or updated in the Map.
**Example 1:
JavaScript `
let GFGMap = new Map();
// Adding a key value pair GFGMap.set(1, "India");
// Getting the value by key console.log(GFGMap.get(1));
// Updating the existing value GFGMap.set(1, "England");
// Getting the value back console.log(GFGMap.get(1));
`
**Output:
India
England
**Example 2: Using set() with chaining
JavaScript `
let myMap = new Map();
// Adding key value pair with chaining myMap.set(1, "Rohan").set(2, "Sohan").set(3, "Trojan");
// Getting the values back console.log(myMap.get(1)); console.log(myMap.get(2)); console.log(myMap.get(3));
`
**Output:
Rohan
Sohan
Trojan
**Supported Browsers:
- Chrome 38
- Edge 12
- Firefox 13
- Opera 25
- Safari 8
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