Ionic 2: Pass param to next page as copy, not by reference

Question

Q) How do I pass my param to the next page as a copy, so that changes to it don't persist in the previous screen when I go back?

e.g.

  showDetails(item) {
    this._nav.push(PersonDetailsPage, {
      person: item
    });    
  }

So when I view the PersonDetailsPage, I want to be able to make changes, cancel, go back and not have the original object modified.

Thanks.

Clone the object and pass the clone. – acdcjunior May 02 '16 at 02:59 — acdcjunior, May 02 '16 at 02:59

score 5 · Answer 1 · answered May 06 '17 at 09:39

5

Use "Object.assign"

let original = { person: items };
let copy = Object.assign({}, original );

answered May 06 '17 at 09:39

Nejc Lepen

357
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score 4 · Accepted Answer · answered May 02 '16 at 08:18

4

For now I've gone with:

var copy = JSON.parse(JSON.stringify(obj));

answered May 02 '16 at 08:18

Dave

5,283
7
44
66

score 1 · Answer 3 · answered May 02 '16 at 06:32

1

In Javascript, objects are passed by reference. Only primatives (number, string, boolean, etc) are passed by value. Your best bet is going to be using the Object.assign method to make a copy of the object.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/assign

answered May 02 '16 at 06:32

Dan Bucholtz

713
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I tried that, unfortunately it doesn't copy nested objects so it's busted. – Dave May 02 '16 at 08:17

Ionic 2: Pass param to next page as copy, not by reference

3 Answers3