how to remove duplicates in array of objects 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: how to remove duplicate array object in javascript

let days = ["senin","senin","selasa","selasa","rabu","kamis", "rabu"];
let fullname = [{name: "john"}, {name: "jane"}, {name: "imelda"}, {name: "john"},{name: "jane"}];

// REMOVE DUPLICATE FOR ARRAY LITERAL
const arrOne = new Set(days);
console.log(arrOne);

const arrTwo = days.filter((item, index) => days.indexOf(item) == index);
console.log(arrTwo);


// REMOVE DUPLICATE FOR ARRAY OBJECT
const arrObjOne = [...new Map(person.map(item => [JSON.stringify(item), item])).values()];
console.log(arrObjOne);

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

Example 4: remove duplicates objects from array javascript

arr.reduce((acc, current) => {
  const x = acc.find(item => item.id === current.id);
  if (!x) {
    return acc.concat([current]);
  } else {
    return acc;
  }
}, []);