16/7/7_php-static Static keyword

Static statically-keyword

Static properties and methods can be called without instantiating the class, directly in the way they are used 类名::方法名 . Static properties do not allow an object to be called with an operator.

Class Car {    private static $speed = ten;        public static function GetSpeed () {        return self:: $speed;    }} Echo Car::getspeed ();  Calling a static method

Static methods can also be dynamically called through variables

$func = ' getspeed '; $className = ' Car '; Echo $className:: $func ();  Dynamic invocation of static methods

In a static method, $this pseudo-variable is not allowed. You can use Self,parent,static to invoke static methods and properties internally.

Class Car {    private static $speed = ten;        public static function GetSpeed () {        return self:: $speed;    }        public static function SpeedUp () {        return self:: $speed +=10;    }} Class Bigcar extends Car {public    static function start () {        parent::speedup ();}    } Bigcar::start (); Echo Bigcar::getspeed ();

16/7/7_php-static Static keyword