Filter null values from a Map in JavaScript-CodePudding

Is it possible to filter null values from a map?

const myMap = new Map<string, string|undefined>([
  ['id1', 'value1'],
  ['id2', null],
  ['id3', 'value3'],
  ['id4', null],
]);

I would like my map with id1 and id4 only because the other ids have null values.

Thanks

CodePudding user response：

You can convert to array, filter and create a map again:

const myMap = new Map([
  ['id1', 'value1'],
  ['id2', null],
  ['id3', 'value3'],
  ['id4', null],
]);
const res = new Map(Array.from(myMap).filter(val => val[1]))

CodePudding user response：

You can use .filter():

const myMapFiltered = new Map([...myMap].filter(([key, value]) => value));

Or if you want to filter in place:

for (let k of myMap.keys()) {
  if (!myMap.get(k))
    myMap.delete(k);
}