php 中 self 和 static 的区别

class Foo{ public static $str = 'This is foo'; public static function show() { echo __METHOD__ . PHP_EOL; echo static::$str; }}class Boo extends Foo{ public static $str = 'This is boo';}Boo::show();# 输出结果# Foo::show# This is boo

使用 static 调用的是当前类的变量

class Foo{ public static $str = 'This is foo'; public static function show() { echo __METHOD__ . PHP_EOL; echo self::$str; }}class Boo extends Foo{ public static $str = 'This is boo';}Boo::show();# 输出结果# Foo::show# This is foo

使用 self 调用的是最高级的父类的变量