JavaScript: size: get number of pairs in map

Every map has a ‘size’ property, it returns the number of <key, value> pairs in the map.

HelloWorld.js

var countries = [["Russia", "Moscow"], ["Spain", "Madrid"]];

var countriesMap = new Map(countries);

countriesMap.set("Bahrain", "Manama");
countriesMap.set("Cameroon", "Yaounde");
countriesMap.set("Norway", "Oslo");
countriesMap.set("India", "New Delhi");

for (var [country, capital] of countriesMap) {
  console.log(country + ' : ' + capital);
}

console.log("Total elements in countriesMap are : " + countriesMap.size);

Output

Russia : Moscow

Spain : Madrid

Bahrain : Manama

Cameroon : Yaounde

Norway : Oslo

India : New Delhi

Total elements in countriesMap are : 6

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