I started to work at the end of December, 19, with nearly one and a half years of work experience
The following notes include small companies, as well as medium and large ones (Doodle, Praise, Didi, Flying Pig, Byte), and you get a lot more job interviews than you do for the first time. But interview nerves remain as strong as ever, especially after an in-person interview and some questions are missed or poorly answered
js
- GetPrototypeOf is different from getAttribute
- Typeof Instanceof distinction, Instanceof implementation
- Base types refer to what types;
How do I determine the type of a variable
- Prototype chain
- Function scope chain
The process of new
- Call Apply procedure (change this to refer to)
- es5
inheritance
; The difference between combinatorial inheritance and prototype chain inheritance - Differences between ES5 inheritance and ES6 inheritance;
What does Super do
; Class class implementation process - The garbage collection
eventloop
Micro task macro task; When will the macro task generated in the microtask be executed?- Deep copy Shallow copy
- If else Switch case optimization
- A decorator
- Design Patterns (Strategic patterns)
- es5
xhr
es6fetch
The difference between - The encodeURI and encodeURICompoent
- Error capture in setTimeout, asynchronous error capture
closure
How to produce and why can access the action malpractice; The addEventListener event is not a closure- Arrow functions are different from normal functions
- For in and for of
- map set
- ForEach Map (How to use forEach Rendering components)
AST syntax tree
- How does HTTP upload files
- Function scope Block – level scope
- var let
- let const
- How to make an object property immutable (defineProperty Writable)
defineProperty
With proxy difference- DefineProperty what other attributes are there
- Can the defineProperty attribute be changed more than once and how can it be changed only once (it can be changed more than once; Sets the signals to false.)
- How to determine if an object is a proxy
- Reflect what is
- This points to the
- What does Bind do, implement
- Symbol (how to generate unique values besides random numbers)
- Promise.all Parallel or sequential
- Promise.all is different from promise. race
- async await
- Calling async without await returns what
- Await a function that is not async, what is returned
- Await plain value or promise, what is returned
- .
- Ts type is different from interface
The browser
- How do I expand the capacity of localStorage
localStorage
与cookie
The difference between- Cookies and
session
The difference between - How sessions are stored
- Does loading JS block page rendering
Throttling stabilization
Implement applicationRearrangement to redraw
; How to avoid redrawing- What does a multi-process browser look like
- Multiple workers will have several processes
- IndexedDB(yes)/ localStorage (no), cookie(no)
- What is a service worker
How do IFrames communicate
What else is there besides postMessage- Disadvantages of using iframe (How to preserve the status bar)
- Advantages of CDN
- svg vs iconfont
- Cross-domain solutions
css
CSS priority
! Important > Inline > id > class- Border 0.5 px.
BFC IFC
Vertical center
- Triangular trapezoid
- Pseudo class pseudo element distinction
- Em rem difference
- Adaptive layout Flexible layout differences
- H5 1px phenomenon, why
- The child element requires a width of 1:1 and increases as the parent element grows, always keeping the child element 1:1
- Parent div (BFC) and child IMG have no width and height limits
- How will the child IMG display
- There is a gap between the sub-img and the div
react
- Class function component difference
Why hook; Hooks are class-based benefits
Why can't hook be written in if
Useeffect replaces the class component which declaration cycle
- React.memo / React.lazy
- Usecallback useMemo difference
- Composite event 16, 17
- React15 16 difference
React Diff algorithm (Single-node multi-node)
- Why can setState update views
- SetState is synchronous or asynchronous
- Parent-child communication
- What are the reasons for the abolition lifecycle
The fiber architecture
; React Fiber’s previous architecture- What properties does a Fiber node have
- Time slice (how to determine whether the current frame has time left)
- Double tree cache
- The react data flow
- React Status Management
React-router type is implemented
- A string with a special placeholder that changes the placeholder to a component
network
- HTTP is different from HTTPS
- HTTPS encryption symmetric asymmetric; Why symmetric encryption
Network attack
(XSS, CSRF), phenomenon, defense, which type- The cache
Status code 401 403 301 302 304
- http2.0
- What are the request and Response headers
- What about multiple posts (what else can be done besides anti-shaking, Axios cancels the last one…)
- Request timing problem, input input, the first request to return the result, if ensure that the data received is correct
algorithm
- Dynamically plan stair climbing
- Back to eight Queens
- Pre-tree middle-order traversal (non-recursive)
- Sort two sorted arrays
- The last KTH of the linked list (time complexity O(n), space complexity O(1))
webpack
- Basic configuration
- tree-shaking
- Babel is the difference between
- Commonjs is different from ES6 modules
- How are hot updates implemented
- What modules will be in common.js
- How to package multiple files
- To optimize the