Programmer Group

Notes on Python basic learning (4)   There are three basic characteristics of object-oriented Encapsulation: abstract and encapsulate objective things into objects, that is, attributes, methods and events are integrated into a whole Inheritance: allows you to use the functions of existing classes and extend them without rewriting the origi ...

Recursion and closures, as an important part of js, are almost involved in front-end interviews, especially closures. Today, the leader of the front-end group asked me a question and gave a rough answer. I felt dissatisfied, so I relearned and wrote this article. Before we talk about these two concepts, let's review function expressions. Func ...

Catalog I. css effect attribute 1.box-shadow​ 2.text-shadow 3.border-radius 4.background Sprite animation Size adaptation of background drawing 5.clip-path Clip path animation: svg effect: 6.3D transformation Transform transform: - chromon rotation: I. css effect attribute box-shadow ...

What is Local? Whether you are exposed to threading.Local or werkzeug.Local, they represent a variable - each thread's own global variable.   Global variables, usually on the process heap. All threads of a process can access the same global variable, because they share the address space of the process, so each thread can access it, which al ...

There are several questions about uploading pictures in the question of thinking or not, all of which involve the concept of ArrayBuffer. I want to sort out the knowledge in this area and hope that more people can get something. Ladies and gentlemen, let's start together. 1. How to upload files Generally, FormData is used to create request data ...

When you're using Lombok's @Data When commenting, there will be some holes that need attention. Let's see today. Lombok Let's briefly introduce Lombok. Its official introduction is as follows: Project Lombok makes java a spicier language by adding 'handlers' that know how to build and compile simple, boilerplate-free, not-quite-java code ...

Easy-POI Tool link Github: https://github.com/programmeres/easy-poi Code cloud: https://gitee.com/nw1992/easy-poi Easy POI is a lightweight open source component of Excel import and export solution. (if you like or are willing to use it, please star and Watch the project. If you are an enterprise, please let me know the name of the enterprise b ...

jquery-svg-pan-zoom.js download and documentation here https://github.com/DanielHoffmann/jquery-svg-pan-zoom Principle: control the viewbox property of svg viewbox is an attribute of SVG image. It defines the visible area of SVG, which is defined by four numbers: abscissa X, ordinate Y, Width, ...

Data hijacking Data hijacking uses Object.defineProperty() to implement the two-way binding of vue. Let's see how it works. let obj = {}, txt = '' Object.defineProperty(obj,'txt',{ set(val) { console.log('set ....') txt = val || ''; }, get() { //get callback will be triggered when getting obj.txt. ...

When we need to define constants, one way is to use uppercase variables to define integers, such as months JAN = 1 FEB = 2 MAR = 3 APR=4 May=5 Jun=6 Jul=7 Aug=8 Sep=9 Oct=10 NOV = 11 DEC = 12 The advantage is simplicity, the disadvantage is the type int, and it is still a variable. A better way is to define a class type for ...