Define object with variables for property names [duplicate]

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How to use a variable for a key in a JavaScript object literal? (16 answers)

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Shorthand way to construct JS object with variable property name [duplicate] (2 answers)

Closed 8 years ago.

I have a problem in declaring a inicialiting an object. When I define an object and pass by reference a string does not recognize me and fails. The object is as follows:

markerGroups = {"america": [], "europa": [], "asia": [],"africa": [], "oceania": [] };

Well, it works correctly, but if I change, for example, "america" ​​putting var amer = "america"​​, like this:

var amer = "america"; 
markerGroups = {amer: [], "europa": [], "asia": [],"africa": [], "oceania": [] };

It does not work. What i have to do for resolve this?

Answer 1

something like this;

var markerGroups = {}
var amer = "america"; 
markerGroups[amer] = [];

Answer 2

In JavaScript, you don't need to quote your object keys. So amer: [] is creating the literal key "amer".

You need to use the [] method to do this:

var amer = "america"; 

markerGroups = {...};
markerGroups[amer] = [];