`Rx.Observable.prototype.forkJoin(...args, [resultSelector])`

Runs all observable sequences in parallel and collect their last elements.

Arguments

args: Arguments | Array - An array or arguments of Observable sequences or Promises to collect the last elements for.
resultSelector: Function - The result selector from all the values produced. If not specified, forkJoin will return the results as an array.

Returns

(Observable): An observable sequence with an array collecting the last elements of all the input sequences or the result of the result selector if specified.

Example

// With a selector
var source = Rx.Observable.just(42).forkJoin(
  Rx.Observable.range(0, 3),
  function (s1, s2) { return s1 + s2; });

var subscription = source.subscribe(
  function (x) {
    console.log('Next: %s', x);
  },
  function (err) {
    console.log('Error: %s', err);
  },
  function () {
    console.log('Completed');
  });

// => Next: 44
// => Completed

// Without a selector
var source = Rx.Observable.just(42).forkJoin(
  Rx.Observable.range(0, 3));

var subscription = source.subscribe(
  function (x) {
    console.log('Next: %s', x);
  },
  function (err) {
    console.log('Error: %s', err);
  },
  function () {
    console.log('Completed');
  });

// => Next: [42, 2]
// => Completed