This article is mainly based on code, and its main purpose is to understand PHP's object-oriented interface (interface) and memos through examples.
Use the interface keyword instead of the class keyword to define an interface;
Constants can be defined in an interface, but member properties and member methods cannot be defined. This is different from abstract classes (abstract classes can be defined)
The methods in the interface are all abstract methods, but they are not modified with the abstract keyword and have no entity content
interface usb{
function connect();//Link USB
function quit(); //Exit USB
interface chapai{
const DIANYA = '220v';
function charu();//Insert
function bachu();//Unplug
}
Take three different electronic devices as an example: Different devices implement USB interfaces in different ways, and thus implement different actions
Digital camera: Plug it into the computer and the picture browser will pop up U-shield: Install Driver, open the browser Mobile phone: charging
class shouji implements usb,chapai{ //A class can implement multiple interfaces
function connetc(){
echo 'Charging mobile phone, displaying mobile phone content' ;
}
function quit(){
echo "The phone stops charging, exit";
}
function charu( ){ //Method to implement plug-in interface通过 Echo "mobile phone through" .Self :: diany. "Charging voltage, storing charging"; Leave ".self::DIANYA."voltage strip";
}
}
class xiangji implements usb{
function connetc(){
echo "camera plug On the USB, display the picture ";
}
" function quit(){
" echo "Camera unplugged";
}
}
class pc{
function usbConnect($usb){ //Pass in different electronic devices, get the device object and then call the link method of this electronic device
$obj = new $usb();
$obj->connect();
using using using using using through using ’’s ’ through out using ’s ’ s ‐ ‐‐‐‐ $ usb (); gt;usbConnectc( 'shouji'); //new a computer object, and when the mobile phone is passed in, it will call the method of connecting the mobile phone to USB
Through the above computer class, it can be understood as:
The mobile phone is connected to the computer through USB, the opportunity Call the method of the mobile phone; when the camera is connected to the computer via USB, the method of the camera will be called
The above has introduced PHP object-oriented examples, including aspects of content. I hope it will be helpful to friends who are interested in PHP tutorials.

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