javascript - Remove items from one array of objects from another array of objects with _.differenceBy

Question

I have two arrays of objects:

var defendantList = [
  {
    label: "Joe BLow"
    value: "Joe Blow"
  },
  {
    label: "Sam Snead"
    value: "Sam Snead"
  },
  {
    label: "John Smith"
    value: "John Smith"
  },
];

var dismissedDefendants = [
  {
    date: 'someDateString',
    value: "Joe Blow"
  },
  {
    date: "someOtherDateString",
    value: "Sam Snead"
  }
];

I need to create an array that has values from defendantList that are not contained in dismissedDefendants. How can I do that simply, either with lodash or a standard JS array function? I'm looking at lodash's _.differenceBy, since it has an iteratee, but I can't quite figure out how.

UPDATE: the desired end result in this example is just an array with the non-matching object:

  var newArray = [
      {
        label: "John Smith"
        value: "John Smith"
      },
    ];

Thanks.

Answer 1

Using _.differenceBy():

_.differenceBy(defendantList, dismissedDefendants, 'value');

var defendantList = [
  {
    label: "Joe BLow",
    value: "Joe Blow"
  },
  {
    label: "Sam Snead",
    value: "Sam Snead"
  },
  {
    label: "John Smith",
    value: "John Smith"
  },
];

var dismissedDefendants = [
  {
    date: 'someDateString',
    value: "Joe Blow"
  },
  {
    date: "someOtherDateString",
    value: "Sam Snead"
  }
];

var result = _.differenceBy(defendantList, dismissedDefendants, 'value');

console.log(result);

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