RxJS:从 Observable.fromPromise 拆分数组结果 [英] RxJS: Splitting an array result from Observable.fromPromise

问题描述

我在这里使用 RxJS，但我似乎无法克服这个看似简单的问题.

I'm using RxJS here and I can't seem to get over this seemingly simple issue.

rx.Observable
    .from([1,2,3,54,3,22,323,23,11,2])
    .distinct()
    .subscribe(function next (x) {
        console.log('Next');
        console.log(x);
    }, function error (x) {
        console.log('Error');
        console.log(x);
    }, function completed () {
        console.log('Completed');
    });

上面的代码按预期顺序吐出每个数组项.

The above code spits out each array item in order as expected.

rx.Observable
    .fromPromise(getNumbers([1,2,3,54,3,22,323,23,11,2]))
    .distinct()
    .subscribe(function next (x) {
        console.log('Next');
        console.log(x);
    }, function error (x) {
        console.log('Error');
        console.log(x);
    }, function completed () {
        console.log('Completed');
    });

function getNumbers (nums) {
    return new Promise(function (resolve, reject) {
        resolve(nums);
    });
}

这里虽然我只得到了完整的数组(即 [ 1, 2, 3, 54, 3, 22, 323, 23, 11, 2 ]).RxJS 不应该把结果分开吗?我希望它至少有一些逻辑.

Here though I only get the full array (i.e. [ 1, 2, 3, 54, 3, 22, 323, 23, 11, 2 ]). Shouldn't RxJS be breaking the result apart? I'd hope it at least had some logic for this.

谢谢

推荐答案

不，它不会隐式地将它们分开.如果要拆分它们，请使用 flatMap 将数组展平:

No it will not break them apart implicitly. If you want to split them use flatMap which will flatten the array:

 rx.Observable
    .fromPromise(getNumbers([1,2,3,54,3,22,323,23,11,2]))
    .flatMap(function(x) { return x; })
    .distinct()
    .subscribe(function next (x) {
        console.log('Next');
        console.log(x);
    }, function error (x) {
        console.log('Error');
        console.log(x);
    }, function completed () {
        console.log('Completed');
    });

这篇关于RxJS:从 Observable.fromPromise 拆分数组结果的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！