how to use includes in javascript array of objects code example

Example 1: how to check if an element exists in an array of objects js

var arr = [{ id: 1, username: 'fred' }, 
  { id: 2, username: 'bill'}, 
  { id: 3, username: 'ted' }];

function userExists(username) {
  return arr.some(function(el) {
    return el.username === username;
  }); 
}

console.log(userExists('fred')); // true
console.log(userExists('bred')); // false

Example 2: angular list contains property

vendors.filter(function(vendor){ return vendor.Name === "Magenic" })