Basic JavaScript questions cover concepts like data types, variables and scoping, array, string manipulation, OOP (Object Oriented Programming), control flow, error handling, DOM manipulation, and asynchronous programming. The basic JavaScript coding interview questions are: ...
Ex: string, number, boolean, or array of objects Example of Array: let arr = [1,2,3] //number array let arr2 = [“a”,”b”,”c”]// string array JavaScript Interview Questions for Experienced 16. What is the JavaScript DOM? The Document Object Model, or DOM, is a map of a...
Object - Used to store collection of data. Example: // Collection of data in key-value pairs var obj1 = { x: 43, y: "Hello world!", z: function(){ return this.x; } } // Collection of data as an ordered list var array1 = [5, "Hello", true, 4.1]; Note- It is importa...
Convert all keys within an object into snake_case/camelCase DOM APIs: document.getElementByClassName(), document.getElementByTagName() Observer patternThe best way to prepare for JavaScript coding questions is to get your hands dirty by implementing them yourself and writing test cases for them....
The difference between a string and an array How to declare a variable Basic arithmetic Functions Loops Right the way through to more advanced concepts such as: Closures DOM manipulation Asychronicity Arrow functions Functional programming Using Object Literals to pass optional arguments ...
We’ll use JavaScript object literals to represent the individual questions and an array to hold all of the questions that make up our quiz app. Using an array will make the questions easy to iterate over:const myQuestions = [ { question: "Who invented JavaScript?", answers: { a: "...
Rich Community Support –React is backed by a massive Developer Community with almost 1.6k contributors on GitHub and a wide array of learning resources, tutorials, and help guides readily available to anyone starting. Also, do not forget React.js is backed by one of the world’s largest and...
Array Cardio Day 2 Day 7 Fundamentals Fun with HTML5 Canvas Day 8 Fun + Experimental 14 Must Know Dev Tools Tricks Day 9 Fundamentals Hold Shift to Check Multiple Checkboxes Day 10 DOM & Interface Custom HTML5 Video Player Day 11
22.What is the difference between Object and Map? 23.What are the mutable and immutable array's methods? 24.What does array-like mean? 25.What is the difference between for...of and for...in loop? 26.What are asynchronous operations?
B: "array" C: "object" D: "NaN" 答案 答案:C 扩展运算符(...args)会返回实参组成的数组。而数组是对象,因此 typeof args 返回"object"。 20. 输出是什么? function getAge() { 'use strict' age = 21 console.log(age) } getAge() A: 21 B: undefined C: ReferenceError D: TypeError ...