Is there a cleaner, more efficient way to have an IF statement that doesn't error on undefined?

Asked Aug 13 '17 at 15:54

Active Jun 05 '19 at 22:18

Viewed 35 times

In my React app, I'm checking for nextProps like so:

  componentWillReceiveProps(nextProps) {
    if (nextProps.invite && nextProps.invite.status) {
    }
  }

I need the above because it's possible nextProps.invite is undefined so if I had just nextProps.invite.status I would get a JS console undefined error...

Is there a cleaner, more efficient way to write the above logic?

edited Jun 05 '19 at 22:18

halfer

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asked Aug 13 '17 at 15:54

AnApprentice

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Not the answer you're looking for - but I see / use this pattern a lot in simple react apps. In something with redux - the conditional checks will probably happen in my reducers / containers before I ever pass the props to my components. – Christopher Messer Aug 13 '17 at 15:58
@ChristopherMesser the one above or did you mean to paste something? – AnApprentice Aug 13 '17 at 15:59
1

Yes, what you've shown above. – Christopher Messer Aug 13 '17 at 16:00
`typeof nextProps.invite !== 'undefined'` or have a initial state in your reducer. – Win Aug 13 '17 at 16:06
1

@bergi shure? I think there are better answers at this case, that would be a good *may have a look at* instead of an exact dupe – Jonas Wilms Aug 13 '17 at 16:18
@Jonasw It might not have the best answers possible, but it's the canonical duplicate for the topic. Do you have other links in mind? – Bergi Aug 13 '17 at 16:30
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@bergi im thinking of a prototype to prevent errors – Jonas Wilms Aug 13 '17 at 16:35
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Can also write it as `(nextProps.invite || {}).status` – csander Aug 13 '17 at 16:46
@Jonasw Well yes not having the property being `undefined` in the first place is usually the best solution, but that's not what was asked for. – Bergi Aug 13 '17 at 18:09

Is there a cleaner, more efficient way to have an IF statement that doesn't error on undefined?

0 Answers0