The 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.
The examples below illustrate the set() method:
Example 1:
Javascript
<script>   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)); </script> |
Output :
India England
Example 2: Using set() with chaining
Javascript
<script>   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)); </script> |
Output :
Rohan Sohan Trojan