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PHP language knowledge: What is a class_PHP tutorial

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Release: 2016-07-21 14:56:01
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Bangkejia (www.Bkjia.com) Tutorial Before elaborating on the concept of classes, let’s first talk about the concept of object-oriented programming: Object-Oriented Programming, abbreviated as OOP ) is focused on creating software that reuses code and has the ability to better simulate real-world environments, making it recognized as a winner in top-down programming. It "encapsulates" functions into "objects" necessary for programming by adding extended statements to the program. Object-oriented programming languages ​​make complex work clear and easy to write. It's a revolution, not in the objects themselves, but in their ability to handle work. Objects are not compatible with traditional programming and programming methods, and being partially object-oriented makes the situation worse. Unless the entire development environment is object-oriented, the benefits of objects may not be as much trouble. Some people may say that PHP is not a true object-oriented programming language. PHP is a hybrid language. You can use object-oriented programming or traditional procedural programming. However, for the development of large projects, you may want to use pure object-oriented programming in PHP to declare classes, and only use objects and classes in your project development. As projects get larger, it may be helpful to use object-oriented programming. Object-oriented programming code is easy to maintain, easy to understand and reuse, which are the basics of software engineering. Applying these concepts in web-based projects becomes the key to future website success.

Object (Object) is an abstraction of something in the problem domain or implementation domain. It reflects the information that this thing needs to save and the role it plays in the system; it is a set of attributes and the right to operate on these attributes. A package of a set of services. Objects should be understood from two aspects: on the one hand, they refer to objects in the real world that the system needs to process; on the other hand, objects are objects that the computer does not directly process, but processes corresponding computer representations. This computer representation is also called an object. To put it simply, a person is an object, and a ruler can also be said to be an object. When these objects can be directly represented by data, we call them attributes. The measurement unit of the ruler can be centimeters, meters or feet. This measurement unit is the attribute of the ruler.

In PHP we can define a class. A class refers to a collection of variables and some functions that use these variables. PHP is a loosely typed language, so overloading by type does not work, nor does overloading by different numbers of parameters. Sometimes it's good to overload constructors in an orientation so that you can create objects in different ways (passing different numbers of arguments). In PHP, this is achieved through classes.

以下为引用的内容:
class Class_name // 在面向对象编程类中,习惯上类的第一个字符为大写,并且必须符合变量的命名规则。
{

//函数与变量的集合

}
?>

The following is the quoted content:
class Class_name // In object-oriented programming classes, it is customary to use the first One character is uppercase and must conform to the variable naming rules.
{

//A collection of functions and variables

}
?>

In PHP, information encapsulation is completed through classes. The syntax for defining classes in PHP is:

以下为引用的内容:
class Student
{
var $str_Name; //姓名
var $str_Sex; //性别
var $int_Id; //学号
var $int_English; //英语成绩
var $int_maths; //数学成绩
}
?>

When defining a class, you can define it in the format you like, but it is best to maintain a standard, so that development will be more efficient.

Data members are defined in the class using the "var" declaration. Before the data members are assigned a value, they have no type. A data member can be an integer, an array, an associated array (Associative Array) or an object.

The following is a practical example of a class definition:

This is a simple example of a very common definition class, which is used to display students’ academic performance. The class name is Student. The Student class contains a student’s basic attributes: name, gender, student ID, English scores, and math scores.

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www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/364298.htmlTechArticleLieHuo.Net tutorial Before elaborating on the concept of classes, let’s first talk about the concept of object-oriented programming :Object-Oriented Programming (OOP) is based on...
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