indexOf method in an object array?

Question

What\'s the best method to get the index of an array which contains objects?

Imagine this scenario:

var hello = {
    hello: \'world\',
    foo: \'ba         


        

Answer 1

Using the ES6 findIndex method, without lodash or any other libraries, you can write:

function deepIndexOf(arr, obj) {
  return arr.findIndex(function (cur) {
    return Object.keys(obj).every(function (key) {
      return obj[key] === cur[key];
    });
  });
}

This will compare the immediate properties of the object, but not recurse into the properties.

If your implementation doesn't provide findIndex yet (most don't), you can add a light polyfill that supports this search:

function deepIndexOf(arr, obj) {
  function findIndex = Array.prototype.findIndex || function (pred) {
    for (let i = 0; i < this.length; ++i) {
      if (pred.call(this, this[i], i)) {
        return i;
      }
    }

    return -1;
  }

  return findIndex.call(arr, function (cur) {
    return Object.keys(obj).every(function (key) {
      return obj[key] === cur[key];
    });
  });
}

(from my answer on this dupe)