To get an index of an object from an array of objects, we can use the findIndex() array method on the array containing the object elements in JavaScript.

TL;DR

// Array of objects
const objsArr = [
  { name: "John Doe", age: 23 },
  { name: "Roy Daniel", age: 25 },
];

// Get the index of the object in the array
const indexOfObject = objsArr.findIndex((obj) => {
  // if the current object name key matches the string
  // return boolean value true
  if (obj.name === "Roy Daniel") {
    return true;
  }

  // else return boolean value false
  return false;
});

console.log(indexOfObject); // 1

For example let's say we have an array of objects like this,

// Array of objects
const objsArr = [
  { name: "John Doe", age: 23 },
  { name: "Roy Daniel", age: 25 },
];

Now, If we want to get the index of the object with the name key that matches Roy Daniel, we can use the findIndex() method.

• the findIndex() requires a function as an argument.
• the argument function will be passed the current array element every time an element is looped.
• Inside this function, we can check if the name matches Roy Daniel and return the boolean value true if it matches and the boolean value false if not.
• the findIndex() method returns the index of the object in the array.

It can be done like this,

// Array of objects
const objsArr = [
  { name: "John Doe", age: 23 },
  { name: "Roy Daniel", age: 25 },
];

// Get the index of the object in the array
const indexOfObject = objsArr.findIndex((obj) => {
  // if the current object name key matches the string
  // return boolean value true
  if (obj.name === "Roy Daniel") {
    return true;
  }

  // else return boolean value false
  return false;
});

console.log(indexOfObject); // 1

That's all 😃!

See the above code live in JSBin

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