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JavaScript JavaScript Loops, Arrays and Objects Tracking Data Using Objects The Student Record Search Challenge Solution

Elizabeth Chai
Elizabeth Chai
9,692 Points
Posted by Elizabeth Chai
Elizabeth Chai
9,692 Points

is there a way to use .indexOf to find an object's value in an array?

for example,

var things= [
 {item: "chocolate", price: "3.45"},
{item: "coffee", price: "3.45"},
{item: "bread", price: "3.45"},
{item: "chips", price: "3.45"}
];

how would you use .indexOf to find "chocolate" or "chips" or even the price? I tried to look this up on MDN but sometimes it's hard to understand the explanations... thanks so much.

2 Answers

Neil McPartlin
Neil McPartlin
14,662 Points
Neil McPartlin
Neil McPartlin
14,662 Points

Hi Elizabeth,

Using indexOf would have been feasible had your array only contained primitive types such as numbers, strings etc. but as your array contains objects, it needs a different approach.

Array.prototype.findIndex()

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/findIndex

So for example, this will work.

things.findIndex(i => i.item === "chips"); // 3

Then having found that chips is located at index 3, the price is found like so.

things[3].price; // '3.45'

But as suggested by James, 'find' may suit your needs better.

Array.prototype.find()

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find

So for this, we first need a simple callback which includes the searched item

function search(things) {
    return things.item === 'chips';
}

Now run this

things.find(search) // { item: 'chips', price: '3.45' }

So with this method, we are not told the index, but we do find the other 'key:value' located at the same index.