js object array remove duplicates code example

Example 1: how to remove duplicate array object in javascript

let person = [{name: "john"}, {name: "jane"}, {name: "imelda"}, {name: "john"}];

function removeDuplicates(data, key) {
  
  return [
    ...new Map(data.map(item => [key(item), item])).values()
  ]

};

console.log(removeDuplicates(person, item => item.name));

Example 2: how to remove duplicate array object in javascript

let person = [
{name: "john"}, 
{name: "jane"}, 
{name: "imelda"}, 
{name: "john"},
{name: "jane"}
];

const data = Array.from(new Set(person.map(JSON.stringify))).map(JSON.parse);
console.log(data);

Example 3: filter duplicate value in array of object typescript

var arrOfObj = [
  {
    id:1 ,name:'abc',age:27
  },
  {
    id:2 ,name:'pqr',age:27
  },
  {
    id:1 ,name:'abc',age:27
  },
 ]

var setObj = new Set(); // create key value pair from array of array

var result = arrOfObj.reduce((acc,item)=>{
  if(!setObj.has(item.age)){
    setObj.add(item.age)
    acc.push(item)
  }
  return acc;
},[]);//converting back to array from mapobject

console.log(result);

Example 4: remove duplicates objects from array javascript

function remove_duplicate_objects(data,prop) {
    var seen = {};
    data = data.filter(function (entry) {
      if (seen.hasOwnProperty(entry[prop])) {
        return false;
      }

      seen[entry.prop] = entry;
      return true;
    });
    return data
  }

const new_array = remove_duplicate_objects([array with objects inside])