我有一个场景，我想调用一个API，如果返回200，我想调用另一个API，但我只对第一个被调用的API的响应感兴趣.大概是这样的:
const http1$ = of('response 1');
// const http2$ = of('response 2');
const http2$ = throwError('response 2');
http1$.pipe(
switchMap((response1) => http2$.pipe(map(() => response1)))
).subscribe(response1 => {
// I need to get response 1 even if http2 fails which, in this case, won't work
console.log(response1);
});
我想到的唯一解决方案是让ATM机在点击或在HTTP1的订阅内订阅HTTP2，但这不是一个好做法.
如果我没理解错的话，在map操作员中"输入"catchError应该可以帮你解决这个问题.
沿着这些思路的一些东西
http1$.pipe(
switchMap((response1) => http2$.pipe(
map(() => response1)).pipe(
catchError(() => of(response1))
)
)
).subscribe(response1 => {
// I need to get response 1 even if http2 fails which, in this case, won't work
console.log(response1);
});
EDIT AFTER THE COMMENT个 相反，如果您想在Http1$返回后触发并忘记Http2$，但对Http2$的结果(忘记部分)完全不感兴趣，并立即返回Http1$的响应，则可以这样进行
// first create a shared stream starting with http1$
const http1Shared$ = http1$.pipe(
share()
);
// then use the shared stream to create a new stream which will trigger http2$ as soon as http1$ returns
// the use of the shared stream is to make sure http1$ is only called once
// you can catch the error and ignore it using catchError(() => EMPTY)
// EMPTY is an observable that completes immediately without emitting any value and without erroring
const stream2$ = http1Shared$.pipe(
switchMap(() => http2$),
catchError(() => EMPTY),
);
// then subscribe to both streams - the first one will be used to process the response from http1$
// the second one will be used to trigger http2$ as soon as http1$ returns but will ignore its response
http1Shared$.subscribe(response1 => {
// I need to get response 1 even if http2 fails which, in this case, won't work
console.log(response1);
});
stream2$.subscribe();