How to compare two arrays when the key is a string - JavaScript

Let’s say the following is our first array −

const firstArray = [
   { "name": "John Doe" },
   { "name": "John Smith" },
   { "name": "David Miller" },
   { "name": "Bob Taylor" },
   { "name": "Carol taylor" },
   { "name": "Adam Smith" },
];

Let’s say the following is our second array −

const secondArray = [
   { "name": "Adam Smith" },
   { "name": "John Doe" },
   { "name": "David Miller" },
   { "name": "James Taylor" }
];

To compare, use map() and includes().

Example

Following is the code −

const firstArray = [
   { "name": "John Doe" },
   { "name": "John Smith" },
   { "name": "David Miller" },
   { "name": "Bob Taylor" },
   { "name": "Carol taylor" },
   { "name": "Adam Smith" },
];
const secondArray = [
   { "name": "Adam Smith" },
   { "name": "John Doe" },
   { "name": "David Miller" },
   { "name": "James Taylor" }
];
const getAllValue = ({ 'name': name }) => name;
const result = firstArray
   .map(getAllValue)
   .filter(value => secondArray
      .map(getAllValue)
      .includes(value)
   );
console.log(result);

 To run the above program, you need to use the following command −

node fileName.js.

Here, my file name is demo251.js

Output

This will produce the following output on console −

PS C:\Users\Amit\javascript-code> node demo251.js
[ 'John Doe', 'David Miller', 'Adam Smith' ]