How to check if the JSON data is one object or an array of objects?

Question

I got server responsed JSON data:

var data = SERVER_RESPONSE;

this data could be an object {id: 12, name: John},

it could also be an array of objects [{id: 12, name: John}, {id: 22, name: OMG}]

In Javascript, how can I check if the JSON data is one object or an array of objects?

Darin Dimitrov · Accepted Answer · 2011-05-06 09:11:58Z

14

You could use the following test:

if (data instanceof Array) {
    // data is an array
} else {
    // it is not an array
}

answered May 6, 2011 at 9:11

Darin Dimitrov

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Comments

Alnitak · Accepted Answer · 2011-05-06 09:12:02Z

2

A simple test is to check for the existence of obj.length and obj[0].

It's not 100% fool proof, but if you know that your data can only appear in one of the two formats you put in the question it should be sufficient.

answered May 6, 2011 at 9:12

Alnitak

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