javascript object array remove duplicates object 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: 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);