let arr1 = [1, 2, 3, 4, 5, 6, 2, 3]
let arr2 = [1, 2, 3, 4, 5, 6, 5, 6]
let result = Array.from(new Set([...arr1, ...arr2]))
console.log(result) // [1, 2, 3, 4, 5, 6]

let arr1 = [1, 2, 3, 4, 5, 6, 2, 3]
let arr2 = [1, 2, 3, 4, 5, 6, 5, 6]
let arr3 = arr1.concat(arr2)
function uniqueFun(arr) {
 const newArr = []
 for (let i = 0; i < arr.length; i++) {
     if (newArr.indexOf(arr[i]) == -1) {
         newArr.push(arr[i])
     }
 }
 return newArr
}
console.log(uniqueFun(arr3)) // [1, 2, 3, 4, 5, 6]

let arr1 = [1, 2, 3, 4, 5, 6, 2, 3]
let arr2 = [1, 2, 3, 4, 5, 6, 5, 6]
let arr3 = arr1.concat(arr2)
function uniqueFun(arr) {
 const newArr = []
 for (let i = 0; i < arr.length; i++) {
     if (!newArr.includes(arr[i])) {
         newArr.push(arr[i])
     }
 }
 return newArr
}
console.log(uniqueFun(arr3)) // [1, 2, 3, 4, 5, 6]

let arr1 = [1, 2, 3, 4, 5, 6, 2, 3]
let arr2 = [1, 2, 3, 4, 5, 6, 5, 6]
let arr3 = arr1.concat(arr2) // [1, 2, 3, 4, 5, 6, 2, 3, 1, 2, 3, 4, 5, 6, 5, 6]
function uniqueFun(arr) {
 return arr.filter((item, index, arr) => {
     return arr.indexOf(item) == index // 返回當(dāng)前元素在原始數(shù)組的索引值 == 當(dāng)前索引值的元素
 })
}
conosle.log(uniqueFun(arr3)) // [1, 2, 3, 4, 5, 6]

let arr1 = [1, 2, 3, 4, 5, 6, 2, 3]
let arr2 = [1, 2, 3, 4, 5, 6, 5, 6]
let arr3 = arr1.concat(arr2) 
function uniqueFun(arr) {
 let map = new Map()
 return arr.filter(item => {
     return !map.has(item) && map.set(item, 1)
 })
}
console.log(uniqueFun(arr3)) // [1, 2, 3, 4, 5, 6]

let arr1 = [{id: 1, name: '小明'}, {id: 2, name: '小紅'}, {id: 4, name: '小劉'}]
let arr2 = [{id: 1, name: '小明'}, {id: 2, name: '小紅'}, {id: 3, name: '小王'}]
let arr3 = [...arr1, ...arr2]
function uniqueFun(arr) {
 const map = new Map()
 return arr.filter(item => {
     return !map.has(item.id) && map.set(item.id, 1)
 })
}
console.log(uniqueFun(arr3)) // 輸出 [{id: 1, name: '小明}, {id: 2, name: '小紅'}, {id: 4, name: '小劉'}, {id: 3, name: '小王'}]

let arr1 = [{id: 1, name: '小明'}, {id: 2, name: '小紅'}, {id: 4, name: '小劉'}]
let arr2 = [{id: 1, name: '小明'}, {id: 2, name: '小紅'}, {id: 3, name: '小王'}]
let arr3 = [...arr1, ...arr2]
function uniqueFun(arr) {
 const obj = {}
 return arr.filter(item => {
     return !obj.hasOwnProperty(item.id) && (obj[item.id] = 1)
 })
}
console.log(uniqueFun(arr3)) // 輸出 [{id: 1, name: '小明}, {id: 2, name: '小紅'}, {id: 4, name: '小劉'}, {id: 3, name: '小王'}]

let arr1 = [{id: 1, name: '小明'}, {id: 2, name: '小紅'}, {id: 4, name: '小劉'}]
let arr2 = [{id: 1, name: '小明'}, {id: 2, name: '小紅'}, {id: 3, name: '小王'}]
let arr3 = arr1.concat(arr2)
function uniqueFun(arr) {
 return arr.reduce((pre, cur) => {
     if (!pre.find(item => item.id === cur.id)) {
         pre.push(cur)
     }
     return pre
 }, [])
}
console.log(uniqueFun(arr3)) // 輸出 [{id: 1, name: '小明}, {id: 2, name: '小紅'}, {id: 4, name: '小劉'}, {id: 3, name: '小王'}]