PHP中static 跟self的使用区别
PHP中static 和self的使用区别
class A {
??? public static function who() {
??? ??? echo __CLASS__;
??? }
??? public static function test() {
??? ??? self::who();
//??? ??? static::who();
??? }
}
A::test();
class B extends A {
??? public static function who() {
??? ??? echo __CLASS__;
??? }
}
echo B::test();
?
如果使用关键字self运行结果：?? A A
如果使用关键字static运行结果：A B
static：父类访问了子类的静态方法
self: 是类内指针，指向本类，静态方法，属性
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