blocks|key|4402644|text|我建议您改用flatMap+(现在rxjs版本5中的mergeMap+)，如果您不关心错误，它将允许您折叠错误。实际上，您将创建一个内部可观察对象，如果发生错误，该对象可以被吞并。这种方法的优点是，您可以将操作符链接在一起，如果管道中的任何地方发生错误，它将自动转发到catch块。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4402645|​|4402646|const+{from,+iif,+throwError,+of,+EMPTY}+=+rxjs;
const+{map,+flatMap,+catchError}+=+rxjs.operators;

//+A+helper+method+to+let+us+create+arbitrary+operators
const+{pipe}+=+rxjs;

//+Create+an+operator+that+will+catch+and+squash+errors
//+This+returns+a+function+of+the+shape+of+Observable<T>+=>+Observable<R>
const+mapAndContinueOnError+=+pipe(
++//This+will+get+skipped+if+upstream+throws+an+error
++map(v+=>+v+*+2),
++catchError(err+=>+{
++++console.log("Caught+Error,+continuing")
++++//Return+an+empty+Observable+which+gets+collapsed+in+the+output
++++return+EMPTY;
++})
)

const+observable+=+from([0,+1,+2,+3,+4,+5]).pipe(
++flatMap((value)+=>+
++++iif(()+=>+value+!=+3,+
++++++of(value),+
++++++throwError(new+Error("Value+cannot+be+3"))
++++).pipe(mapAndContinueOnError)
++)
);

observable.subscribe(
++(value)+=>+console.log("onNext+"+%2B+value),+(error)+=>+console.log("Error:+"+%2B+error.message),+()+=>+console.log("Completed!")
);|code-block|syntax|javascript|4402647|<script+src="https://unpkg.com/rxjs@7.0.0/dist/bundles/rxjs.umd.min.js"></script>|4402648|4402649|entityMap^0|6|7|Q|8|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@$9|S|A|T|B|C]|$9|U|A|V|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|W|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|X|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|J|7|Y|8|@]|D|@]|E|$K|L]]|$1|O|3|G|5|6|7|Z|8|@]|D|@]|E|$]]|$1|P|3|-4|5|6|7|10|8|@]|D|@]|E|$]]]|Q|$]]

<p>I would suggest that you use <code>flatMap</code> (now <code>mergeMap</code> in rxjs version 5) instead, which will let you collapse errors if you don't care about them. Effectively, you will create an inner Observable that can be swallowed if an error occurs. The advantage of this approach is that you can chain together operators and if an error occurs anywhere in the pipeline it will automatically get forwarded to the catch block.</p>
<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="true">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>const {from, iif, throwError, of, EMPTY} = rxjs;
const {map, flatMap, catchError} = rxjs.operators;

// A helper method to let us create arbitrary operators
const {pipe} = rxjs;

// Create an operator that will catch and squash errors
// This returns a function of the shape of Observable&lt;T&gt; =&gt; Observable&lt;R&gt;
const mapAndContinueOnError = pipe(
  //This will get skipped if upstream throws an error
  map(v =&gt; v * 2),
  catchError(err =&gt; {
    console.log("Caught Error, continuing")
    //Return an empty Observable which gets collapsed in the output
    return EMPTY;
  })
)

const observable = from([0, 1, 2, 3, 4, 5]).pipe(
  flatMap((value) =&gt; 
    iif(() =&gt; value != 3, 
      of(value), 
      throwError(new Error("Value cannot be 3"))
    ).pipe(mapAndContinueOnError)
  )
);

observable.subscribe(
  (value) =&gt; console.log("onNext " + value), (error) =&gt; console.log("Error: " + error.message), () =&gt; console.log("Completed!")
);</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://unpkg.com/rxjs@7.0.0/dist/bundles/rxjs.umd.min.js"&gt;&lt;/script&gt;</code></pre>
</div>
</div>
</p>


blocks|key|4402469|text|您需要切换到一个新的可处理流，如果其中发生错误，将被安全地处理，并保持原始流存活：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4402470|​|4402471|Rx.Observable.from([0,1,2,3,4,5])
++++.switchMap(value+=>+{

++++++++//+This+is+the+disposable+stream!
++++++++//+Errors+can+safely+occur+in+here+without+killing+the+original+stream

++++++++return+Rx.Observable.of(value)
++++++++++++.map(value+=>+{
++++++++++++++++if+(value+===+3)+{
++++++++++++++++++++throw+new+Error('Value+cannot+be+3');
++++++++++++++++}
++++++++++++++++return+value;
++++++++++++})
++++++++++++.catch(error+=>+{
++++++++++++++++//+You+can+do+some+fancy+stuff+here+with+errors+if+you+like
++++++++++++++++//+Below+we+are+just+returning+the+error+object+to+the+outer+stream
++++++++++++++++return+Rx.Observable.of(error);
++++++++++++});

++++})
++++.map(value+=>+{
++++++++if+(value+instanceof+Error)+{
++++++++++++//+Maybe+do+some+error+handling+here
++++++++++++return+`Error:+${value.message}`;
++++++++}
++++++++return+value;
++++})
++++.subscribe(
++++++(x+=>+console.log('Success',+x)),
++++++(x+=>+console.log('Error',+x)),
++++++(()+=>+console.log('Complete'))
++++);|code-block|syntax|javascript|4402472|<script+src="https://cdnjs.cloudflare.com/ajax/libs/rxjs/5.4.1/Rx.min.js"></script>|4402473|4402474|有关此技术的更多信息，请参阅此博客文章：The+Quest+for+Meatballs:+Continue+RxJS+Streams+When+Errors+Occur|offset|length|4402475|entityMap|0|LINK|mutability|MUTABLE|url|https://iamturns.com/continue-rxjs-streams-when-errors-occur/?ref=so&refId=38649652^0|0|0|0|0|0|K|1S|0|0^^$0|@$1|2|3|4|5|6|7|X|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Y|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Z|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|F|7|10|8|@]|9|@]|A|$G|H]]|$1|K|3|C|5|6|7|11|8|@]|9|@]|A|$]]|$1|L|3|M|5|6|7|12|8|@]|9|@$N|13|O|14|1|15]]|A|$]]|$1|P|3|-4|5|6|7|16|8|@]|9|@]|A|$]]]|Q|$R|$5|S|T|U|A|$V|W]]]]

<p>You need to switch to a new disposable stream, and if an error occurs within it will be disposed safely, and keep the original stream alive:</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>Rx.Observable.from([0,1,2,3,4,5])
    .switchMap(value =&gt; {

        // This is the disposable stream!
        // Errors can safely occur in here without killing the original stream

        return Rx.Observable.of(value)
            .map(value =&gt; {
                if (value === 3) {
                    throw new Error('Value cannot be 3');
                }
                return value;
            })
            .catch(error =&gt; {
                // You can do some fancy stuff here with errors if you like
                // Below we are just returning the error object to the outer stream
                return Rx.Observable.of(error);
            });

    })
    .map(value =&gt; {
        if (value instanceof Error) {
            // Maybe do some error handling here
            return `Error: ${value.message}`;
        }
        return value;
    })
    .subscribe(
      (x =&gt; console.log('Success', x)),
      (x =&gt; console.log('Error', x)),
      (() =&gt; console.log('Complete'))
    );</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://cdnjs.cloudflare.com/ajax/libs/rxjs/5.4.1/Rx.min.js"&gt;&lt;/script&gt;</code></pre>
</div>
</div>
</p>

<p>More info on this technique in this blog post: <a href="https://iamturns.com/continue-rxjs-streams-when-errors-occur/?ref=so&amp;refId=38649652" rel="noreferrer">The Quest for Meatballs: Continue RxJS Streams When Errors Occur</a></p>


blocks|key|4402704|text|为了避免你的endlessObservable$死掉，你可以把你的failingObservable$放在一个更高阶的映射运算符中(例如switchMap，concatMap，exhaustMap...)并通过使用不返回值的empty()+observable终止内部流来接受错误。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4402705|使用RxJS+6：|4402706|endlessObservable$
++++.pipe(
++++++++switchMap(()+=>+failingObservable$
++++++++++++.pipe(
++++++++++++++++catchError((err)+=>+{
++++++++++++++++++++console.error(err);
++++++++++++++++++++return+EMPTY;
++++++++++++++++})
++++++++++++)
++++++++)
++++);|code-block|syntax|javascript|4402707|entityMap^0|6|I|X|I|1W|9|26|9|2G|A|34|7|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]|$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]|$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|11|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|12|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|13|8|@]|D|@]|E|$]]]|N|$]]

<p>To keep your <code>endlessObservable$</code> from dying you can put your <code>failingObservable$</code> in a higher-order mapping operator (e.g. <code>switchMap</code>, <code>concatMap</code>, <code>exhaustMap</code>...) and swallow the error there by terminating the inner stream with an <code>empty()</code> observable returning no values.</p>
<p>Using RxJS 6:</p>
<pre><code>endlessObservable$
    .pipe(
        switchMap(() =&gt; failingObservable$
            .pipe(
                catchError((err) =&gt; {
                    console.error(err);
                    return EMPTY;
                })
            )
        )
    );
</code></pre>


<p>I have a list of items to parse, but the parsing of one of them can fail.</p>

<p>What is the "Rx-Way" to catch error but continue executing the sequence</p>

<p>Code Sample:</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>var observable = Rx.Observable.from([0,1,2,3,4,5])
.map(
  function(value){
      if(value == 3){
        throw new Error("Value cannot be 3");
      }
    return value;
  });

observable.subscribe(
  function(value){
  console.log("onNext " + value);
  },
  function(error){
    console.log("Error: " + error.message);
  },
  function(){
    console.log("Completed!");
  });</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://cdnjs.cloudflare.com/ajax/libs/rxjs/4.0.6/rx.all.js"&gt;&lt;/script&gt;</code></pre>
</div>
</div>
</p>

<p>What I want to do in a non-Rx-Way:</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>var items = [0,1,2,3,4,5];

for (var item in items){
  try{
    if(item == 3){
      throw new Error("Value cannot be 3");
    }
    console.log(item);
  }catch(error){
     console.log("Error: " + error.message);
  }
}</code></pre>
</div>
</div>
</p>

<p>Thanks in advance</p>


RxJs catch error and continue

我有一个要解析的项目列表，但其中一个项目的解析可能会失败。捕获错误但继续执行序列的"Rx-Way“是什么代码示例：​var observable = Rx.Observable.from([0,1,2,3,4,5]).map(  function(value){      if(value == 3){        ...

问RxJ捕获错误并继续
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