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Try to access instance variables directly inside the object When reading data inside an object, it should be read directly through instance variables, while when writing data, it should be written through attributes. _name = @"Jack" does not send messages through setter, and directly assigns values to variables, which is fast. For t ...

I. Introduction to pixi.js pixi.js is a very fast 2D sprite rendering engine. It can help us display, animate and manage interactive graphics. In this way, we can easily implement an application or complete a game using javascript and other HTML5 technologies. It has a semantic, concise API, and contains many useful functions. For example, it s ...

JavaScript arrays are used to store multiple values in a single variable. Example var cars = ["Saab", "Volvo", "BMW"]; What is an array? Arrays are special variables that can store more than one value at a time. If you have a list of items (for example, a list of car brands), storing car brands in a single variable should look like t ...

# Edition python==3.7.3 selenium==4.0.0a1 # selenium pypi address https://pypi.org/project/selenium/ Catalog:I. Initialization2. Element Search3. select Label Operation4. Executing js scripts5. iframe operation6. Action and Action ChainVII. Abnormal handlingVIII. Withdrawal Procedure I. Initialization from selenium import webdriver fr ...

1.Ioc (inversion of control) controls inversion (an idea). IoC is an idea. Before that, the creation of objects used in programs must be completed by programmers. IoC entrusts the creation, preservation and management of objects (life cycle) to Spring, so Spring is also equivalent to a container (object of objects stored), which is the process ...

scene In development, there are often constants, fields, attributes, methods of global scope. These need to be set to global scope to save and have unique instances. Note: Blog Home Page: https://blog.csdn.net/badao_liumang_qizhi Focus on the Public Number A hegemonic programmed ape Get programming related e-books, tutorials and free down ...

Demand point In many scenarios, the information can not be easily modified. When modifying, it needs either permission or approval. However, in either way, the data before and after modification needs to be kept "background". That is to say, the key information is modified with modification records. Generally, modification records re ...

Previously, the execution sequence of static code blocks, construction code blocks, common code blocks, and class initialization has not been particularly clear. Here, collate, facilitate review! Execution order: Parent class - > subclass Static Attribute - Static Code Block - > Common Attribute - Constructing Code Block - > Construc ...

I. Introduction of Lodash: Lodash is a set of tool library, which encapsulates many processing functions for common data types, such as strings, arrays, objects and so on, to help developers reduce the difficulty of using JS. Introduction to Lodash: Take Vue-cli as an example: 1,yarn install lodash2. Introduce and use in main.js import _ from ' ...

Preface Through the combination of HTML5 and OpenLayers, a very good application of telecommunication map network topology can be formed. The result can be used as a telecommunication resource management system, food location sharing software, area room search, railway line drawing and so on. It is an application that can be involved in all fi ...