Filter JSON object to remove keys

Asked May 28 '16 at 00:04

Active May 28 '16 at 00:04

Viewed 31 times

I have an Angular 2 app which gets some values from an API (which I can't control) using a promise. The JSON returned is like this:

[{"Id":1053},{"Id":1054},{"Id":1103}]

However, my app only needs to consume an array of numbers i.e. what I need to consume is this:

[1053,1054,1103]

Here's the part of my app which gets the data from the API:

recordIds = [];

ngOnInit() { 
    this._contentService.getAncestorNodes(currentNodeId).then(
        (data) => {
            data.map(function(record){
                console.log('record.Id = ' + record.Id);
            });
        }
    );
}

I've tried adding this.recordIds.push(record.Id) into the data.map function to try to build a new object of just the Ids, but I just get the following error:

Cannot read property 'recordIds' of undefined

Question is, how can I take the response from the API and parse it into the desired format?

Many thanks.

asked May 28 '16 at 00:04

Dan

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Because `this` has different context in `map()` – charlietfl May 28 '16 at 00:09
Ah, that makes sense, but how do I push to the `recordIds` array from inside the map function then? – Dan May 28 '16 at 00:14
Store reference to `this`. Or simply use the `return` of `map()` – charlietfl May 28 '16 at 00:16
I see from here: http://stackoverflow.com/questions/30148827/this-is-undefined-inside-map-function-reactjs that I can pass `this` as a parameter after the map function, and this sorts it. Thanks! – Dan May 28 '16 at 00:17
Or just use an arrow function. – Felix Kling May 28 '16 at 00:33

Filter JSON object to remove keys

0 Answers0