Check if struct is empty: Javascript

Question

I have a list of items showing up on a page, using a struct. If a customer doesn't choose on of those items, I want to check if the struct is empty or not.

Here is my code:

shopItems.shopItemsStruct = {};

so when I do console.log(shopItems.shopItemsStruct) when I don't select a item, it shows me Object { }. How do I check in an if statement (ie if shop items are not selected)?

Thanks.

Duplicate - http://stackoverflow.com/questions/679915/how-do-i-test-for-an-empty-javascript-object — bwegs, Jan 20 '16 at 20:45
Object { 24: Object} and Object { 24: Object, 25: Object} if it has more items — Udaan, Jan 20 '16 at 20:46

score 6 · Accepted Answer · edited Jan 23 '16 at 15:53

6

The function Object.keys returns an array of keys in the object it is passed as a parameter. If the returned value is zero then the object has no keys.

if (Object.keys(shopItems.shopItemsStruct).length === 0) {
    ...
}

edited Jan 23 '16 at 15:53

ndugger

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answered Jan 20 '16 at 20:47

HBP

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score 1 · Answer 2 · answered Jan 20 '16 at 20:47

1

It is an object; a key value set. Just look for the presence of keys.

if( !Object.keys(shopItems.shopItemsStruct).length ){
 //no shop items selected                            
}

answered Jan 20 '16 at 20:47

Travis J

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Check if struct is empty: Javascript

2 Answers2