object oriented javascript interview questions

Boolean), then the method is no longer created. In short, the method usesFlag (_initialized) to determine if any method has been given to the prototype. This method is created and assigned only once, and traditional OOP developers are happy to sendNow, this code looks more like a class definition in other languages.What kind of approach should we adopt?as mentioned earlier, the most widely used is the hybrid constructor/prototype approach. In addition, the dynamic prototyping method is also ver

nil. if an object's class does not implement an initializer, the Objective-C runtime invokes the initializer of the nearest ancestor instead. It means that two steps 1 are required to allocate memory 2 for initialization to create an object. 1. allocate memory. sent alloc orallocWithZone: message to the object's class. This is the common [Class alloc]. Or the uncommon [Class allocWithZone]. 2 initialization. You need to call the init Method for initi

I encountered an interview question today to request that an object be allocated at the specified void * pmem in the memory so that the object can be stored at pmem. I am not doing this anymore. The record is as follows. By default, the new operator placement of objects is used to create an object in free memory. If y

A single selection1. Which of the following statements will produce A run: (A)A.var obj = ();B.var obj = [];C.var obj = {};D.var obj =//;b is the array, C is the object, and D is the regular expression2. Which of the following words does not belong to JavaScript reserved words: (B)A. WithB. ParentC. ClassD. void abstract break · byte case · Catch char · Class const · Con

with Java, you may have some questions about the introduction function. Java programmers will not add this all the time. This will be added only when a whim occurs. However, if you want to be lazy in JavaScript and remove this, the result will only be an error. What's going on? In short, the this keyword here is essential! This is a difference between JavaScript

. Conversely, when Getfullname () is assigned to the test variable, the context refers to the Global Object (window). This is because test is a property that is implicitly set to the global object. For this reason, the function returns the FullName of the window, that is, the value defined in the first row.Question 5:call () and apply ()Now let you solve the previous problem and make the final Console.log (

Good questions about object-oriented analysis and design. it may take some time for the younger brother to get in touch with object-oriented design. every time you design a new system, you will encounter problems about how to split and design objects, let's talk about it. Fo

is followed, the parser will automatically fill the semicolon (;), so the second function above will become like this:Function foo2 () {return; {bar: "hello "};}So the second function returnsUndefined.7. Is Shenma NaN, and its type is Shenma? How to test whether a value is NaN?NaNIs the abbreviation of Not a Number. a special value of JavaScript, which is of the Number type.IsNaN (param)To determine whether a value isNaN:Console. log (isNaN

. You don't have to worry about maintaining complicated external states.For example, in python, we have made a lot of tricks on closures:Static private variable ~Partial function ~Single parameter ~Decorator ~...... When using these features, you are actually eating the "instant noodles" set by others ". In fact, I understand that closures are used to expand the scope of variables. What is the relationship between immediate function execution and closure? Let's take a look at @ Bian Cheng's u

Heroes Good, little brother contact object-oriented also has a period of time, can each design a new system will encounter on the object how to split and design problems, special to consult. For example, the current system requirements are: users, roles, points. Users are: User name, password. Roles are: role names. Points are: The integral value, the owning user

() {} person. Prototype. Name = "Nicolas" ; Proson. Prototype. Age = 29 ; Person. Prototype. sayname = Function () {Alert ( This . Name );} VaR Person1 = New Person (); person1.sayname (); // "Nicolas" VaR Person2 = New Person (); person2.sayname (); // "Nicolas" Alert (person1.sayname = Person2.sayname ); // True We add the sayname () method and all attributes directly to the prototype attribute of person, and the constructor becomes an empty function. Even so, we can still call

The last two sections talk about JavaScript object-oriented namespaces and JavaScript-oriented JavaScript classes, so you can look at the above and continue to look down. In fact, it is very simple, less talk, read the following

the execution has completed.Input Sample:3 31 1 1 2 0 1 2 1-1-11Sample output:7time limit: 500ms memory limit: 32000kb Import Java.util.scanner;public class Cellmachine {static Scanner in = new Scanner (system.in); static int width = 0;//width st atic int height = 0;//height static int[][] field_old;//old grid static int[][] field_new;//new mesh static int times;//steps Public stat IC void Main (string[] args) {//First enter two positive integers with a range of [3,102], which in turn represent

This article mainly introduces how to implement the inheritance of javascript and how to learn javascript object-oriented. If you are interested, refer to the examples in this article to introduce 6 methods for implementing the inheritance of javascript, the content is as fo

Article category: Web Front-endI. multiple choice questions 1. Which of the following statements will generate a running error :()A. var obj = ();B. var obj = [];C. var obj = {};D. var obj = //; 2. Which of the following words does not belong to a reserved javascript word :()A.B. parentC. classD. void 3. Select a true expression :()A. null instanceof ObjectB. null === undefinedC. null = undefinedD. NaN = Na

Questions about function call variables var a =10; function aaa(){ alert(a); } function bbb(){ var20; //10 } bbb(); Variable declaration issues function aaa(){ var a=b=10; } aaa(); alert(a);//not defined alert(b);//10 Variable lookup is the nearest principle to find, Var defined variables, when the nearest is not found, will look for the outer layer: var10 funct

JavaScript Interview Requirements: the following questions must be selected from one to four, three questions, implemented using native code, cannot be usedIn any framework, the fifth question is selected.1. display images in a fixed area of the page1. Each time you click the right arrow, the image area will scroll to

inheritance in n multiple ways, but keep in mind that you should not use the __proto__ attribute when inheriting, because it is not as reliable as you think. If you want to get a prototype of an object, then this method can be done, object.getprototypeof. Corresponding to this is the Object.setprototypeof method.You may also say that the Object.setprototypeof method can be inherited away from the __proto__. If you were to see the source code, would y

Php object-oriented question ??? Classfactory {private $ tmp = array (); function _ construct () {} publicfunctiont () {array_push ($ this- gt; tmp, 3);} publicfunctiongett () {ret php object-oriented question ??? Class factory { Private $ tmp = array (); Function _ construct (){} Public function t (){ Array_push