Web Front-end
JS Tutorial
Differences in usage of JavaScript isPrototypeOf and hasOwnProperty (practical)Differences in usage of JavaScript isPrototypeOf and hasOwnProperty (practical)
Friends who need tips on using JavaScript isPrototypeOf and hasOwnProperty can refer to it.
1. isPrototypeOf
isPrototypeOf is used to determine whether the specified object object1 exists in the prototype chain of another object object2. If so, it returns true, otherwise it returns false.
The format is as follows:
object1.isPrototypeOf(object2);
object1 is an instance of an object;
object2 is another object whose prototype chain will be checked.
The prototype chain can be used to share functionality between different instances of the same object type.
If the prototype chain of object2 contains object1, then the isPrototypeOf method returns true.
If object2 is not an object or object1 does not appear in the prototype chain in object2, the isPrototypeOf method will return false.
Usage examples are as follows:
var re = /^\s*/;
// Define a regular expression object here
// Check whether RegExp is the prototype chain object of re , returns true
var bIsptt = RegExp.prototype.isPrototypeOf(re);
2. hasOwnProperty hasOwnProperty determines whether an object has a named attribute or object. This method cannot check the Whether the object has this property in its prototype chain, the property must be a member of the object itself.
If the property or method is defined by the object itself rather than in the prototype chain, return true; otherwise, return false;
The format is as follows:
object.hasOwnProperty(proName);
Judgement The name of proName is not a property or object of the object object. Usage examples are as follows:
// Get false because the properties in the prototype chain cannot be detected
var bStr = "Test String".hasOwnProperty("split");
// The prototype of the String object This property already exists, so it naturally returns true
var bStr1 = String.prototype.hasOwnProperty("split");
// Returns true because it is not detecting the property in the prototype
var bObj = ({ fnTest:function(){}}).hasOwnProperty("fnTest");
The above is what I compiled for everyone. I hope it will be helpful to everyone in the future.
Related articles:
Focus on explaining the __proto__ attribute in JavaScript (pictures and texts) Tutorial)
The above is the detailed content of Differences in usage of JavaScript isPrototypeOf and hasOwnProperty (practical). For more information, please follow other related articles on the PHP Chinese website!
Python vs. JavaScript: Community, Libraries, and ResourcesApr 15, 2025 am 12:16 AMPython and JavaScript have their own advantages and disadvantages in terms of community, libraries and resources. 1) The Python community is friendly and suitable for beginners, but the front-end development resources are not as rich as JavaScript. 2) Python is powerful in data science and machine learning libraries, while JavaScript is better in front-end development libraries and frameworks. 3) Both have rich learning resources, but Python is suitable for starting with official documents, while JavaScript is better with MDNWebDocs. The choice should be based on project needs and personal interests.
From C/C to JavaScript: How It All WorksApr 14, 2025 am 12:05 AMThe shift from C/C to JavaScript requires adapting to dynamic typing, garbage collection and asynchronous programming. 1) C/C is a statically typed language that requires manual memory management, while JavaScript is dynamically typed and garbage collection is automatically processed. 2) C/C needs to be compiled into machine code, while JavaScript is an interpreted language. 3) JavaScript introduces concepts such as closures, prototype chains and Promise, which enhances flexibility and asynchronous programming capabilities.
JavaScript Engines: Comparing ImplementationsApr 13, 2025 am 12:05 AMDifferent JavaScript engines have different effects when parsing and executing JavaScript code, because the implementation principles and optimization strategies of each engine differ. 1. Lexical analysis: convert source code into lexical unit. 2. Grammar analysis: Generate an abstract syntax tree. 3. Optimization and compilation: Generate machine code through the JIT compiler. 4. Execute: Run the machine code. V8 engine optimizes through instant compilation and hidden class, SpiderMonkey uses a type inference system, resulting in different performance performance on the same code.
Beyond the Browser: JavaScript in the Real WorldApr 12, 2025 am 12:06 AMJavaScript's applications in the real world include server-side programming, mobile application development and Internet of Things control: 1. Server-side programming is realized through Node.js, suitable for high concurrent request processing. 2. Mobile application development is carried out through ReactNative and supports cross-platform deployment. 3. Used for IoT device control through Johnny-Five library, suitable for hardware interaction.
Building a Multi-Tenant SaaS Application with Next.js (Backend Integration)Apr 11, 2025 am 08:23 AMI built a functional multi-tenant SaaS application (an EdTech app) with your everyday tech tool and you can do the same. First, what’s a multi-tenant SaaS application? Multi-tenant SaaS applications let you serve multiple customers from a sing
How to Build a Multi-Tenant SaaS Application with Next.js (Frontend Integration)Apr 11, 2025 am 08:22 AMThis article demonstrates frontend integration with a backend secured by Permit, building a functional EdTech SaaS application using Next.js. The frontend fetches user permissions to control UI visibility and ensures API requests adhere to role-base
JavaScript: Exploring the Versatility of a Web LanguageApr 11, 2025 am 12:01 AMJavaScript is the core language of modern web development and is widely used for its diversity and flexibility. 1) Front-end development: build dynamic web pages and single-page applications through DOM operations and modern frameworks (such as React, Vue.js, Angular). 2) Server-side development: Node.js uses a non-blocking I/O model to handle high concurrency and real-time applications. 3) Mobile and desktop application development: cross-platform development is realized through ReactNative and Electron to improve development efficiency.
The Evolution of JavaScript: Current Trends and Future ProspectsApr 10, 2025 am 09:33 AMThe latest trends in JavaScript include the rise of TypeScript, the popularity of modern frameworks and libraries, and the application of WebAssembly. Future prospects cover more powerful type systems, the development of server-side JavaScript, the expansion of artificial intelligence and machine learning, and the potential of IoT and edge computing.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

Zend Studio 13.0.1
Powerful PHP integrated development environment

SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.





