js update map value code example

Example 1: append to map javascript

var myMap = {};

myMap[newKey] = newValue;

// ...


// Another method

var myMap = new Map()
myMap.set("key0","value")
// ...
myMap.has("key1"); // evaluates to false, assuming key1 wasn't set

Example 2: node map has value

let myMap = new Map();

myMap.set("key1", "value1");
myMap.set("key2", "value2");

console.log(myMap.has("key1")); // true
console.log(myMap.has("key2")); // true

console.log(myMap.get("key1")); // value1
console.log(myMap.get("key2")); // value2

// NOTE: DO NOT try to access map values using [].
// myMap["key1"] = "value1";