Check if one element exists in an array of objects

Question

I have the following array of objects:

var memberships = [
  {
    id: 1,
    type: 'guest'
  },
  {
    id: 2,
    type: 'member'
  }
];

How can I verify if such an array has at least one element with type 'member'?

Note that the array can also have no elements.

Answer 1

Use array.some()

var memberships = [{
    id: 1,
    type: 'guest'
  },
  {
    id: 2,
    type: 'member'
  }
];

var status = memberships.some(function(el) {
  return (el.type === 'member');
});

/*
  // Simplified format using arrow functions
  var status = memberships.some(el => el.type === 'member')
*/
console.log(status);

Array.some()

Array.some() executes the callback function once for each element present in the array until it finds one where callback returns a truthy value. If such an element is found, some() immediately returns true. Otherwise, some() returns false.