Remove Items From One Array Of Objects From Another Array Of Objects With _.differenceBy

I have two arrays of objects: var defendantList = [ { label: 'Joe BLow' value: 'Joe Blow' }, { label: 'Sam Snead' value: 'Sam Snead' }, { label: 'John

Solution 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);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.2/lodash.min.js"></script>

And an ES6 solution based on Array.prototype.filter() and Set:

defendantList.filter(function({ value }) { 
  return !this.has(value); // keep if value is not in the Set
}, new Set(dismissedDefendants.map(({ value }) => value))); //create a Set of unique values in dismissedDefendants and assign it to this

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 = defendantList.filter(function({ value }) { 
  return !this.has(value); 
}, new Set(dismissedDefendants.map(({ value }) => value)));

console.log(result);

Solution 2:

Here's a simple solution using plain Javascript. Hope it helps!

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"
  }
];

for(var i in defendantList){
    for(var j in dismissedDefendants){
      if(defendantList[i].value === dismissedDefendants[j].value){
        var index = defendantList.indexOf(defendantList[i]);
        if (index > -1) {
        defendantList.splice(index, 1);
        }
      }
    }
}
console.log(defendantList);