调用内部订阅是个好方法吗? [英] Is it good way to call subscribe inside subscribe?
本文介绍了调用内部订阅是个好方法吗?的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我需要将来自三个不同API的三个数据传递给一个函数:
I need to pass three data to one function from three different APIs:
this.service.service1().subscribe( res1 => {
this.service.service1().subscribe( res2 => {
this.service.service1().subscribe( res3 => {
this.funcA(res1, res2, res3);
});
});
});
在订阅中进行订阅是一种好习惯吗?
Is it a good practice to subscribe inside a subscribe?
推荐答案
正确的方法是以某种方式组合各种可观察对象,然后订阅整个流程—如何组成它们取决于您的确切要求.
The correct way is to compose the various observables in some manner then subscribe to the overall flow — how you compose them will depend on your exact requirements.
如果可以同时完成所有操作:
If you can do them all in parallel:
forkJoin(
this.service.service1(), this.service.service2(), this.service.service3()
).subscribe((res) => {
this.funcA(res[0], res[1], res[2]);
});
如果每个都取决于上一个的结果:
If each depends on the result of the previous:
this.service.service1().pipe(
flatMap((res1) => this.service.service2(res1)),
flatMap((res2) => this.service.service3(res2))
).subscribe((res3) => {
// Do something with res3.
});
...等等.构成可观察对象的运算符有很多.
... and so on. There are many different operators to compose observables.
这篇关于调用内部订阅是个好方法吗?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!
查看全文