前言
前几篇介绍过了
Conditional and Boolean Operators
这篇继续介绍 Mathematical and Aggregate Operators
参考
Docs – Mathematical and Aggregate Operators
count
complete 以后, 统计之前总共发布了几次
const subject = new Subject<number>();
subject.pipe(count()).subscribe({
next: v => console.log('next', v),
complete: () => console.log('complete'),
});
subject.complete();
效果
如果一次都没有, 也会 next value 0 哦
max & min
complete 后, 找出之前发布过最大/最小的值
const subject = new Subject<{ age: number }>();
subject.pipe(max(person => person.age)).subscribe({
next: v => console.log('next', v),
complete: () => console.log('complete'),
});
subject.next({ age: 50 });
subject.next({ age: 72 });
subject.next({ age: 40 });
subject.complete();
效果
这里我只给 max 的例子, min 就是找最小.
reduce
一句话总结
count : complete 后统计之前总共发布几次
max & min : complete 后, 找出之前发布过最大/最小值
reduce :
标签：Mathematical,complete,max,Operators,next,Aggregate,subject From： https://www.cnblogs.com/keatkeat/p/17284593.html