Javascript setting uniqueId() as array keys

Question

Should be a simple answer, could be that my syntax is not correct since I am new to ReactJS. I would like to assign a unique id as the key.

This throws an error:

rows:{
  uniqueId() : { name:"Kitchen Remodel", value:20100 },
  uniqueId() : { name:"Basement Remodel", value:8300 }
}

This does not? Please explain...

rows:{
  143434 : { name:"Kitchen Remodel", value:20100 },
  984578 : { name:"Basement Remodel", value:8300 }
}

Thanks!

_the array of objects in an object_? You can make your example work in new and modern JS by using `[uniqueId()]` so that the name of the key is evaluated, but I don't really understand what your goal is. — Tom Fenech, Mar 16 '17 at 16:02
This question doesn't seem to be anything specific to ReactJS, and it seems to already have some answers here: http://stackoverflow.com/questions/2274242/using-a-variable-for-a-key-in-a-javascript-object-literal — Candy Gumdrop, Mar 16 '17 at 16:02

score 2 · Accepted Answer · answered Mar 16 '17 at 16:01

2

In ES6, you can use a function call or variable for the property name like so:

rows:{
  [uniqueId()] : { name:"Kitchen Remodel", value:20100 },
  [uniqueId()] : { name:"Basement Remodel", value:8300 }
}

answered Mar 16 '17 at 16:01

MrCode

I thought there was some syntax issue. I am using ES6 this is a good solution. – Paul Mar 16 '17 at 16:05

score 0 · Answer 2 · answered Mar 16 '17 at 15:58

0

Left hand side cannot be evaluated, when you are declaring an object like this.

You might want to do declare/assign like below

var row = {}; 
row[unique_id()] = { name:"Kitchen Remodel", value:20100 };
row[unique_id()] = { name:"Basement Remodel", value:8300 };

answered Mar 16 '17 at 15:58

Umang Gupta

I see. I did not know it could not be something evaluated, that makes perfect sense. Thanks for the explanation. – Paul Mar 16 '17 at 15:59
This is more a JS (language) phenomenon than React (library). You might want to edit/update your question. – Umang Gupta Mar 16 '17 at 16:00
I was not sure if it was an issue with the uniqueId() function. – Paul Mar 16 '17 at 16:04

2 Answers2