Php object-oriented-class Constants

Php object-oriented-class Constants

Php object-oriented-class Constants

Class constant: in the class, data that remains unchanged during the running period is saved.

Definition:

Const keyword

Const constant name = constant value

Example:

Class Student

{

Public $ stu_id;

Public $ stu_name;

Public $ stu_gender;

Const GENDER_MALE = 'male ';

Const GENDER_FEMALE = 'femal ';

}

Class constants are not restricted by access modifiers.

Access:

Class: constant name

Example:

Class Student

{

Public $ stu_id;

Public $ stu_name;

Public $ stu_gender;

Const GENDER_MALE = 'male ';

Const GENDER_FEMALE = 'femal ';

Public function _ construct ($ id, $ name, $ gender = '')

{

$ This-> stu_id = $ id;

$ This-> stu_name = $ name;

$ This-> gender = ($ gender = '')? Self: GENDER_MALE: $ gender;

}

}

Summary: Members that can be defined in the class, including constants, static attributes, non-static attributes, static methods, and non-static methods.

Note: $ this indicates the current object, always indicates the object of the class where $ this is located?

No, because the value of $ this does not depend on the class where $ this is located, but on the execution object (Execution Environment) when the $ this method is called)

The execution environment of the method, in which the current method is executed

$ This indicates the object.