Applied for front-end intern in junior year

hikvision

One side (Telephone interview 6/10)

  1. This section describes the project technology stack

  2. The role of the typeof

Used to determine the type of a variable

  1. type of null

Returns the object

  1. Array methods

Stack queue :push,pop, Shift,unshift; Traverse: forEach, map; splice,slice

  1. Js basic data type

Undefined,Null,Boolean,Number,String

  1. $router and $route in Vue

$router = $router

  • $route is the “routing information object”, including path, Params, Hash, Query, fullPath, matched, name and other routing information parameters. $router is a “router instance” object that includes hop methods, hook functions, etc
  1. The appearance and function of BFC

Create a rule: Root element, float element (float is not none), absolute position element (position is absolute or fixed),display value is inline-block, table-cell, table-caption, flex, inline-FL Element that is one of ex,overflow does not take the value visible

What it does: Can contain floating elements that are not overwritten by floating elements, preventing margin folding of parent and child elements

  1. Difference between V-if and V-show
  2. Computed is different from Watch

Computed is a property that relies on other properties to compute values, and computed values are cached and returned only when computed values change. Watch listens for a change in the value and executes a callback, in which logical operations can be performed. So generally, computed can be used when you need to rely on other attributes to get values dynamically, and Watch can be used when you need to do some complex business logic to listen for changes in values. In addition, both Computer and Watch support object writing, which is not widely known

  1. Transfer values between components
  2. Multi – page rendering SSR effect

Cool knorr

One side (Telephone interview 6/3)

  1. To introduce myself

omit

  1. OSI network Layering

Physical layer, data link layer, network layer, transmission layer, session layer, presentation layer, application layer

  1. Connection and disconnection of HTTP requests

Three handshakes and four waves

  1. Url to page presentation process

DNS parsing, HTTP requests, and browsers getting data to render pages.

  1. How does DNS resolve

Don’t know

  1. How do browsers render HTML into pages

Parse HTML documents, construct DOM trees, download resources, construct CSSOM trees, execute JS scripts

  1. The child element is centered

Margin written dead, flex layout vertical horizontal center, absolute layout left: 0; top: 0; right: 0; bottom: 0; Margin :auto, absolute layout, top,left,transform: translate move to center, parent element using display: table; Use display: table-cell for child elements; vertical-align: middle; .

  1. How is inheritance implemented in ES5?

Answered only the prototype chain… There are constructors, combinatorial inheritance, mediation of empty objects, and parasitic combinatorial inheritance

  1. How do you understand closures? What do closures do?

The answer was not so good

  1. Talk about the difficulties of the project

The combined use of localStorage and VUex solves the problem of page refresh, state data preservation when reopening, and cross-domain problems.

  1. Benefits of SSR multi-page applications

The first screen rendering is fast and conducive to SEO

  1. webpack

The CLI of vUE is generally used

  1. Talk about quicksort

Briefly

  1. How many ways can ten yuan find one yuan, fifty fen, or ten fen?

Nervous did not come up with a method, the interview is over. And then I thought I was stupid.

function countChange(money) {
    if(money < 0)
        return 0
    else if(money === 0)
        return 1
    else
        returnCountChange (money-1) + countChange(money-0.5) + countChange(money-0.1)}Copy the code

Jingdong for

One side (Telephone interview 5/27)

  1. Introduce the project
  2. How does Vue data render to page work?
  3. Components can pass values in several ways

Props, EMIT, $child, $Parents, Event Bus, vuex

  1. What method does it take to get data from the front end to the back end

cookie

  1. Principle of event broker

Event capture bubbles

  1. Webpack use
  2. Application of binary tree

The role of binary trees, the time complexity of binary search trees

  1. Class A network, Class B network, and Class C network IP address
  2. The role of vuex
  3. The difference between a single-page application and a multi-page application
  4. Have you unit tested your project?
  5. The child form is centered relative to the parent form
  6. Mysql Master level