1. Calling of member attributes and member methods
Inside the class:
$this->member attribute name;
$this->Member method name();
Outside the class:
Object -> member attribute name;
Object->Member Method Name();
2. The definition and use of class constants
Definition: const constant name = constant value
Suggestion: Capitalize constant names
use:
Within the class:
self:: constant name
Class name:: constant name
Outside the class:
Class name:: constant name
3. Static members
Static member properties and static member methods
Definition: static
Use of static member properties:
Within the class:
self::Static member attribute name
Class name:: static member attribute name
Outside the class:
Class name:: static member attribute name
Static member method use:
Within the class:
self::Static member method name();
Class name:: static member method name ();
Outside the class:
Class name:: static member method name ();
4. Static member properties
Static member attributes belong to the class and are shared by the object, not to the object
5. Static member method
1. Static member attributes can be used in ordinary member methods
2. Only static member attributes can be used in static member methods, not non-static member attributes
6、$this
Means: this object (the object that calls this method)
Methods used in the class
7, new process
1. Apply for memory and generate objects
2. If there is a constructor, execute the constructor
3. Return the reference of the object
8. Assignment of objects
The assignment of an object does not generate a new object, but only increases the reference of the variable to the object. If one of them changes, the others will also change accordingly.