design patterns elements of reusable object oriented software book pdf

PHP object-oriented programming and design patterns (4 ). PHP advanced programming study notes exceptions are often used to handle various types of errors encountered during normal program execution. For example, when you do database links, you need to process several PHP advanced programming learning notes for 2014.06

About object-oriented design patterns

Chapter8_math instance, the Add method, which is declared as PUBILC in the parent class, is clearly overridden in the subclass.Of course, when we were wondering about "Case 3", we might have overlooked that "case 3" was created as a math instance, so from the compilation to the heap is a typical parent class, so this is not the overriding operation at all.Now, there is a key point to the static method problem of the static modification,The sub method, which is now declared static, is obviously

that it is a solution to the problem and a simple solution to the complicated problem. This is just a macro description of him. Specifically, the design model is a reusable solution for software design issues in a certain environment. The purpose is to make full use of existing software development experience to solve different problems. During software developm

Enhance code reusability. From the creation of reusable code, reusable code is encapsulated by refactoring from existing code to make it a reusable code block with a single function. In general, this sentence is "encapsulation" or "abstraction ". In actual programming and development, we can create a method to implement code reuse instead of copying the same cod

static method can be executed by a class without having to instantiate it as an object.The role of the----> method is to access and change the properties of an object, sometimes the method simply encapsulates the algorithm, and executing the method does not alter the object's properties, and in object-oriented, the principle is that an object's properties should

modified the class it belongs to.Strategy: Define a series of algorithms, encapsulate them one by one, and make them interchangeable with each other. This mode allows the algorithm to be changed independently of the customer using it.Templatemethod: Defines the skeleton of an algorithm in an operation, and delays some steps into subclasses. Templatemethod allows subclasses to redefine some specific steps of the algorithm without altering the structure of an algorithm.Visitor: Represents an oper

the design pattern, the code is all design patterns, and the most important, the core of the object, are submerged in various patterns. So, there are three main elements in the entire object