前阵子面试做的,拍了下来现在手码给大家,原共45道单选题,限30分钟,现去掉几道概念背诵题和白痴题,保留代码题;仅保留题目,无选项
1:
const promise1 = Promise.resolve('1')
const promise2 = Promise.resolve('2')
const promise3 = Promise.reject('3')
const promise4 = Promise.resolve('4')
const run = async () => {
const res1 = await Promise.all([promise1, promise2])
const res2 = await Promise.all([promise3, promise4])
return [res1, res2]
}
run().then(res => console.log(res))
.catch(err => console.log(err))
输出什么
2:
String.prototype.give = () => {
return 'haha'
}
const name = 'fish'
name.give()
输出什么
3:
function test(){
return 'haha'
}
const test2 = () => 'xixixi'
console.log(test.prototype)
console.log(test2.prototype)
输出什么
4:
function test(a, b){
const forma = new Intl.NumberFormat('en-US', {style: 'unit', unit: 'mile-per-hour'}).format(a)
const forma2 = new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD'}).format(b)
return `test ${forma} haha ${forma2}`
}
console.log(test(130, 300))
输出什么
5:
const test = {name: a}
console.log(test.color[1])
输出什么
6:
let list = [1,2,3].push(4)
console.log(list.push(5))
输出什么
7:
function test(p1, p2 = p) {
if(p1 !== p2) {
console.log('aaa')
} else {
console.log('bbb')
}
}
const p = {name: 'fish'}
test(p)
输出什么
8:
parseInt('7*6', 10)
输出什么
9:
const info = {
[Symbol('a')]: 'b'
}
console.log(info)
console.log(Object.keys(info))
输出什么
10:
class P {
constructor(name) {
this.name = name
}
}
const a = new P('fish')
console.log(typeof a)
输出什么
11:
function test(a, b) { return a + b}
// 是否为纯函数
12:
Number(2) === Number(2)
Boolean(false) === Boolean(false)
Symbol('foo') === Symbol('foo')
T or F ?
13:
const aList = ['a', 'b', 'c'];
({item: aList[3]} = {item: 'd'})
console.log(aList)
输出什么
14:
function test(){
console.log('aaa')
}
test.name = 'fish'
输出什么
15:
// js全局执行上下文为你做了两件事:全局对象和this关键字
// 错、对、看情况
16:
let num = 10;
const fa = () => num++;
const fb = number => number++;
const num1 = fa()
const num2 = fb(num1)
console.log(num1)
console.log(num2)
输出什么
17:
const add = x => x + x;
function test(num = 2, value = add(num)) {
console.log(num, value)
}
test()
test(3)
输出什么
18:
const pp = {
name: 'fish',
value: ['a']
}
function add(a, b = pp.value) {
b.push(a)
return b
}
add('bb', [])
add('cc')
add('dd', pp.value)
console.log(pp.value)
输出什么
19:
function test(a, b, c) {
console.log(a)
console.log(b)
console.log(c)
}
const p1 = 'fish'
const age = 21
test`${p1} is ${age} hahaha`
输出什么
20:
const obj = {
1: 'a',
2: 'b',
3: 'c'
}
const set = new Set([1,2,3,4]);
obj.hasOwnProperty('1')
obj.hasOwnProperty(1)
set.has('1')
set.has(1)
// T or F ?
21:
const value = {number : 10}
const fun = (x = {...value}) => {
console.log(x.number *= 2)
}
fun()
fun()
fun(value)
fun(value)
输出什么
22:
// 下面哪些是false
0
new Number(0)
('')
(' ')
new Boolean(false)
undefined
23:
const name2 = 'fish'
console.log(name2())
输出什么
24:
const teams = [ {name: 'fish', value: ['aa', 'bb']},
{name: 'bee', value: ['cc', 'dd']},
]
function* getValue(value){
for(let i = 0; i < value.length; i++) {
yield value[i]
}
}
function* getTeams(teams){
for(let i = 0; i < teams.length; i++) {
// 要怎么填,才能确保输出以下打印
}
}
const obj = getTeams(teams)
obj.next() // {value: 'aa', done: false}
obj.next() // {value: 'bb', done: false}
25:
class Bird {
constructor() {
console.log('aaa')
}
}
class bb extends Bird {
constructor() {
console.log('bbb')
super()
}
}
const pet = new bb()
输出什么?
26:
var status = 'a'
setTimeout(()=>{
const status = 'b'
const data = {
status: 'c',
getStstus() {
return this.status
}
}
console.log(data.getStstus())
console.log(data.getStstus.call(this))
}, 0)
输出什么
27:
const getList = ([x, ...y]) => [x, y]
const getUser = user => {
return { name:user.name, age: user.age }
}
const list = [1,2,3,4]
const user = {
name: 'fish',
age: 21
}
console.log(getList(list))
console.log(getUser(user))
输出什么
28:
var a1 = 10, a2 = 20;
alert("a1+a2="+a1+a2)
输出什么
这份笔试题我挂了的,60分及格,原共45道,限时30分钟,刚好我53分,虽然是选择题,很多代码题我都得细读再回忆知识点,说到底还是基础差,但也有部分题让我感到很莫名其妙,做半小时后都还有十多道题没填,直接摆烂把题都拍下来~