我正在使用rxjs在有角度的应用程序中构建搜索和过滤系统。
我有以下内容:
interface User{ //exmaple model
_id: string;
name: string;
}
filters$ = new BehaviorSubject<Array<User>>([]);
search$ = new BehaviorSubject<Array<User>>([]);
// I use these two and merge them in another function as following
const myData$ = merge(this.search$.asObservable(), this.filters$.asObservable())
.pipe(distinctUntilChanged(distinctCheck))
使用实用程序功能distinctCheck
类似于:
const distinctKey = (elem) => {
if(elem === null){
return elem
}
if(this.hasId(elem)){
return elem["_id"];
}
if(this.hasName(elem)){
return elem["name"]
}
return this.createComparisonString(elem)
}
但是这使我可以观察到另一个。所以我的问题是:
如何合并两个可观察对象,并仅发出两个数组共有的值?有时候filter $可能会发出30个元素的数组。有时search $可能仅发出2个元素的数组?
IE:
如果filter$
包含:
[{_id:'1', name:'jhon'},{_id:'2', name:'doe'},{_id:'3', name:'jolly'},{_id:'4', name:'some random dude'},{_id:'5', name:'some random other dude'},{_id:'6', name:'johny'},{_id:'7', name:'bravo'}]
和search$
包含:
[{_id:'1', name:'jhon'},{_id:'101', name:'myDoe'},{_id:'301', name:'some-jolly'},{_id:'4', name:'some random dude'}, {_id:'7', name:'bravo'}]
我希望myData$
发出类似的内容:
[{_id:'1', name:'jhon'},{_id:'4', name:'some random dude'}, {_id:'7', name:'bravo'}]
谢谢大家! :)
类似这样的方法应该起作用:
const filters$ = new BehaviorSubject<Array<{ id: string }>>([]);
const search$ = new BehaviorSubject<Array<{ id: string }>>([]);
const combinedAndFiltered$ = combineLatest(filters$, search$)
.pipe(map(([filters, searches]) => {
return filters.filter(filter => !!searches.find(search => search.id === filter.id));
}));
combinedAndFiltered$.subscribe(console.log)
compare
运算符的distinctUntilChanged
函数用于判断先前的发射是否不同于当前的发射。
您实际上可以使用普通的Javascript实现。