in angular5, I cannot access methods in a foreach loop

Question

When I get an array of objects with httpClient, I can access properties of each object in the array, but I cannot access methods. I don't understand why, and how can I do this.

this.interventionService.getInterventions().subscribe(interventions =>
        { 
            interventions.forEach(it => {

               console.log(it.InterventionId); // property can be accessed
               console.log(it.myMethod()); // myMethod cannnot be accessed

               // I get an error: 'myMethod is not a function'

            });
        });

However, if I create a new object, I can access the methods:

var it = new Intervention();
it.myMethod(); // no error

Thanks for help

You need something like: `... .getInterventions().map(items => items.map(i => new Intervention(i)).subscribe ...` — Andrei Tătar, Apr 19 '18 at 13:37
Use interfaces instead of classes for your models. Put the methods in services. — Matt, Apr 19 '18 at 13:37
You have to manually map your object to your class. Angular httpClient just parses data to object. It knows nothing about your methods — yurzui, Apr 19 '18 at 13:42
See also related question https://stackoverflow.com/questions/37310511/how-to-map-a-response-from-http-get-to-a-new-instance-of-a-typed-object-in-angul — yurzui, Apr 19 '18 at 13:44

score 0 · Answer 1 · answered Apr 19 '18 at 13:34

0

You need to set the correct this context for the method using bind.

this.interventionService.getInterventions().subscribe(interventions => {
  interventions.forEach(it => {
      it.myMethod.bind(it)();
  });
});

answered Apr 19 '18 at 13:34

Tomasz Kula

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What if he also does something in the constructor... or has getters/setters on that Intervention class? – Andrei Tătar Apr 19 '18 at 13:35

in angular5, I cannot access methods in a foreach loop

1 Answers1