Convert an array of objects with a unique id property to a Map

Question

I have an array of objects, where each object has a unique member called id. How do I create a Map where the id if the Map\'s key?

Answer 1

You could map a new array in the needed format for the Map.

var array = [{ id: 1, value: 'one' }, { id: 2, value: 'two' }, { id: 3, value: 'three' }, { id: 4, value: 'four' }, { id: 5, value: 'five' }],
    map = new Map(array.map(a => [a.id, a]));

console.log([...map]);

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Or iterate and add the new item to a certain key

var array = [{ id: 1, value: 'one' }, { id: 2, value: 'two' }, { id: 3, value: 'three' }, { id: 4, value: 'four' }, { id: 5, value: 'five' }],
    map = new Map();

array.forEach(a => map.set(a.id, a));
console.log([...map]);

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