Question

在RxJs 5.4.3中如何实现类似于.ofArrayChanges()可以实现的模式？（这不是5.4.3中的功能）

var arr = [1,2,3];
var source = Rx.Observable.ofArrayChanges(arr);

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

arr.push(4)

RxJs .from operators docs

Answer 1

由于Array.observe已过时，我建议您在RxJS中建模整个州。以下是文档中的教程 - Creating applications with RxJS

为您的案例实施：

＆＃13;

const onPush$ = new Rx.Subject();
const onChange$ = new Rx.Subject();

const initialValue = [1, 2, 3];
const series$ = Rx.Observable
  .merge(
    onPush$.map(value => 
      series => {
        series.push(value);
        return series;
      }
    ),
    onChange$.map(({ index, value }) => 
      series => {
        series[index] = value;
        return series;
      }
    )
  )
  .scan(
    (series, makeNew) => makeNew(series),
    initialValue
  );
  
  
series$.subscribe(v => console.log(v));

console.log('push 10');
onPush$.next(10);

console.log('change 0th to be 9');
onChange$.next({ index: 0, value: 9 });

console.log('push 1000');
onPush$.next(1000);

＆＃13;

<script src="https://unpkg.com/rxjs/bundles/Rx.min.js"></script>

＆＃13;

另一个hacky但仍然可能的解决方案是使用ES6 Proxy。类似的东西 - Getter/setter on javascript array?

RxJS中的.ofArrayChanges（）替代方案5.4.3

1 个答案: