javascript object oriented programming interview questions

JavaScript Object-Oriented programming notes

Comments are very detailed, there is no more nonsense, directly on the code: Another paragraph: This article is here first, and later we continue to discuss JavaScript object-oriented programming, I hope you can enjoy.

override property are available on the object that was created before the full overrideIn full rewrite form dog.prototype = {P1:888,p2:999};var Lucy = new Dog ();//New Object for (I-Lucy) {alert (i);//tail P1 p2}for (i in Benji {alert (i);//tail say}4. The above content is still relatively good understanding,Partially overridden property (or method), after overriding the old and new objects can be used, th

[i] = = = ' object ') { C[i] = (P[i].constructor = = = = Array)? [] : {}; Deepcopy (P[i], c[i]); } else { C[i] = P[i]; }} return C;} Use this to write: var Doctor = deepcopy (Chinese); Now, add an attribute to the parent object, and the value is an array. Then, modify this property on the child object: chinese.b

functions to add events to an object by using a function as a value object as a parameter input method and programming method. Of course, you can declare variables separately to reference an anonymous function object, which is no different from a common famous function. function Each(array, fun) { for (var i

. function Deepcopy (p, c) { var c = C | | {}; for (var i in P) { if (typeof p[i] = = = ' object ') { C[i] = (P[i].constructor = = = = Array)? [] : {}; Deepcopy (P[i], c[i]); } else { C[i] = P[i]; }} return C;} Use this to write: var Doctor = deepcopy (Chinese); Now, add an attribute to the parent object, and the value is an array. Then, modify

;} Use this to write: var Doctor = deepcopy (Chinese); Now, add an attribute to the parent object, and the value is an array. Then, modify this property on the child object: chinese.birthplaces = [' Beijing ', ' Shanghai ', ' Hong Kong ']; Doctor.birthPlaces.push (' Xiamen '); At this point, the parent object will not be affec

Javascript is an Object-Based programming language. It is often said that everything in javascript is an Object. How does one generate an Object? (1) original mode First, let's talk about our common

"Inheritance is another important concept of object-oriented development. It can map concepts of real life Program Logical ". "Although there is no special mechanism in JavaScript to implement class inheritance, you can copy the prototype of a class to another class to implement inheritance ". We can see how straightforward the concept inherited here is. "Copy p

= = = = Array)? [] : {}; Deepcopy (P[i], c[i]); } else { C[i] = P[i]; }} return C;} Use this to write: var Doctor = deepcopy (Chinese); Now, add an attribute to the parent object, and the value is an array. Then, modify this property on the child object: chinese.birthplaces = [' Beijing ', ' Shanghai ', ' Hong Kong ']; Doctor.birthPlaces.push (' Xiamen ')

Chapter 1th Introduction1.1 Review History1.2 Winds of Change1.3 Analysis Status1.4 Looking to the future1.5 Object-Oriented programming1.5.1 objects (collections of properties and methods)1.5.2 Class (common characteristics of similar objects, such as sparrows, eagles are birds)1.5.3 Encapsulation (a collection of properties and methods, as well as the concept of a closed scope, such as encapsulating a pla

encapsulates the code of an object and then returns the object that was created.Secure constructor Mode: follows a pattern similar to the parasitic constructor, but the instance method of the newly created object does not reference this and does not call the constructor with the new operator.3. InheritanceNative chain: Use the prototype to have one reference typ

properties and methods of the parent object into the child object, you can also implement inheritance.First, all the invariant properties of animal are placed on its prototype object.function Animal () {} Animal.prototype.species = "Animal";Then, write a function that implements the purpose of the property copy.function Extend2 (Child, Parent) {var p = Parent.prototype;　　　　var c = Child.prototype;　　　　　　for

in toy) {Each object has a isprototypeof method that determines whether the current object is a prototype of another object/*every object also gets the isPrototypeOf () method. * This method tells your whether that specific object is used as a prototype of another

( This. name);}functionSubtype (name,age) {Supertype.call ( This, name);//inherit the Supertype property, passing a name parameter This. age=Age ;} Subtype.prototype=Newsupertype;//Inheritance MethodSubType.prototype.sayAge=function() {alert ( This. age);} Let S1=NewSubtype ("Anna", 23); s1.sayname;//AnnaS1.sayage;// ats1.color//["Red", "green", "blue"]2 Parasitic inheritancefunction=object.create (original);//Create a Parasitic object//give the

untyped objects using curly brace syntaxIts syntax is:{ property1:statement, property2:statement, ..., propertyn:statementn}Here, you implement the definition of an object by using braces to make multiple properties or methods a group.Example: Creating an object with curly brace syntax4.prototype objectsEach function is actually an object, and their

We can see how straightforward the concept inherited here is. "Copy prototype of a class to another class". Good, Code is cheap, and check the Code:Function class1 (){}Function class2 (){}Class2.prototype = class1.prototype;Class2.moreProperty1 = "class 2 additional string ";Class2.moreMethod1 = function () {alert ("class 2 additional method ");}/*In this way, class2 has the same prototype as class1. without considering constructors, the two classes are equivalent.Then, two additional methods we

instance and the prototype is a pointer, not a copy.6. If the prototype is modified to another object, it is tantamount to cutting off the connection between the constructor and the original prototype.7. Currently the most widely used method of creating custom classes in ECMAScript is constructors and prototype compositing patterns.8. Relationship of constructors, prototypes, and instances: each constructor has a prototype

time, because the Syaname method does not currently exist, the syntax block in if is executed, the Sayname method is placed on the shared object prototype, and when the person object is later instantiated, Because the Sayname property already exists, it is not created.Parasitic constructors: (parasitic constructors are similar to factory patterns, except for a new one)function person (name, age) { var o

variable declaration when processing a conflict, will be ignored.Function　　Lexical scope (Lexical environment): Every call, produces a Lexical environment;1, the parameters of the first function: such as arguments(function inside the object, representing the function arguments, can be obtained by the subscript call function simultaneous argument);2. Scan variables after function declaration (Var declaration);3, the processing function declaration has