comparing and removing duplicate between two arrays

by 420

JavaScript

const arr1 = []

const arr2 = [
  {
      userid: "100", 
      projectid: "10",
      rowid: "0"
  },
  {
      userid: "101", 
      projectid: "11",
      rowid: "1"},
  {    
      userid: "102", 
      projectid: "12",
      rowid: "2"},
  {    
      userid: "103", 
      projectid: "13",
      rowid: "3"
  }
]


const arr = arr2.concat(arr1);
const a = [...new Map(arr.map(v => [v.projectid, v])).values()]
console.log('****', a)

//console.log(arr2.filter(val => val.userid !== arr1.userid))