interface keyword

One: abstract methods1. Abstract methods in object-oriented programming languages refer to methods that have only method declarations and no concrete method bodies. Abstract methods generally exist in abstract classes or interfaces.In some parent

Unit Unit1; //unit file name Interface//This is the interface keyword, which is used to identify the cell file that the file is calling uses//common modules used by the program Windows, Messages, sysutils, variants, Classes, Graphics, Controls,

An interface is another way to define a data type. It is very similar to the class.The same: There are member variables and member methodscan also form an inheritance relationshipDifferences: Properties in an interface are constants (final)The

? Classes and objects ? Concepts of classes and objects Class: An objective, abstract, conceptual thing. A class can be defined as a template describing the behavior;Objects: Objects are concrete, practical, and represent

Multiple inheritance (multiple inheritance) refers to the ability of a class to derive from two or more base classes.The CLR does not support multiple inheritance, and the CLR simply provides multi-inheritance of the "shrunk version" through the

Interface Isolation principleOne: What is an interface?Instance interface (Object Interface)---->person zhangsan=new person () produces an instance, the standard that the instance is to follow is the person class, the person class is the interface

Overview of annotations (annotation):• Starting with JDK5.0, Java adds support for metadata (MetaData), which is annotation (annotations)· Annotation is actually a special tag in the code that can be read at compile, class load, run time, and

Single Duty principle (Responsibility Principle) Each object in the system should have only one separate responsibility, and all objects are concerned with the completion of their own duties. A reasonable class provides only one function to the

Abstract class-relatedabstract class: also called abstract base class: A generic class that is marked with the abstract keyword when defined. He can contain features that are contained in a generic class, such as fields, properties, methods, and a

Source: http://blog.sina.com.cn/s/blog_4d65c19e0100bfkb.htmlabstract class: also known as abstract base class: Can contain all the attributes contained in a generic class, for example, fields, properties, methods, abstract classes cannot be

1PHP2 //interface keyword for defining interfaces3 Interfaceicaneat{4 //the method inside the interface does not need to implement the method5 Public functionEat$food) ;6 }7 //The implemaents keyword is used to indicate that a class

The difference between PHP abstract classes and interfaces Introduction: This is an interview often asked questions, but also a classic question. We try to use the official authority's instructions or experiment to prove the accuracy of

This article is mainly code-based, the main role is to understand the PHP object-oriented interface (interface) and memo through an example. Define the interface using the interface keyword, not using the class keyword; You can define constants in

Object-oriented programming (OOP) is a computer programming architecture. One basic principle of OOP is that a computer program is composed of a single unit or object that can act as a subroutine. OOP has achieved three main objectives of Software

Differences between interfaces and abstract classes-what are the differences between roucheng interfaces and abstract classes? What is the basis for using interfaces and abstract classes? The concepts of interfaces and abstract classes are

Interface PHP class is a single inheritance, that is, do not support multiple inheritance, when a class requires multiple classes of functionality, inheritance is powerless, and for this reason PHP introduced interface technology If all the methods

Objects in php include a lot of content, such as the most commonly used php classes, interfaces, polymorphism magic methods (: _ construct (), _ destruct (), _ clone), and so on. the declared instance code of the class is as follows :? Php

PHP5 object-oriented interface technology details. PHP5 also supports the interface concept and introduces the interface and implements keywords for it. Like Java, PHP5 uses interfaces to achieve the same effect as "multi-inheritance. The PHP5

Objects in php include a lot of content, such as the most common php classes, interfaces, polymorphism magic methods (: _ construct (), _ destruct (), and _ clone. Class declaration: Objects in php include a lot of content, such as the most commonly

Preface today, I suddenly thought of a revolution on the official PHP website and saw the announcement of PHP5 at a glance. Although I have seen the predictions of PHP5 before, I carefully read the new features of PHP5/ZendEngine2.0, and I came