JavaScript - get index of object in array by property

In this article, we would like to show you how to get the index of object in an array by property using JavaScript.

Reusable function

In this example, we create a reusable arrow function that accepts three arguments: 

• array that we want to search,
• property that we're looking for,
• value of the property.

The method returns the index of the first object that matches the criteria or -1 if not found.

Practical example:

// ONLINE-RUNNER:browser;

const getObjectIndex = (array, property, value) => {
    for (let i = 0; i < array.length; ++i) {
        if (array[i][property] === value) {
            return i;
        }
    }
    return -1;
};


// Usage example:

const food = [
    { name: 'Apple',    type: 'fruit' },
    { name: 'Broccoli', type: 'vegetable' },
    { name: 'Banana',   type: 'fruit' },
    { name: 'Fries',    type: 'fast-food' },
    { name: 'Cherry',   type: 'fruit' },
];

console.log(getObjectIndex(food, 'type', 'fruit'));     // 0
console.log(getObjectIndex(food, 'type', 'vegetable')); // 1

console.log(getObjectIndex(food, 'name', 'Banana'));    // 2
console.log(getObjectIndex(food, 'name', 'Fries'));     // 3

console.log(getObjectIndex(food, 'name', 'Orange'));    // -1