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HomeBackend DevelopmentPHP TutorialPHP的static与Java的static的对比

在Java中类的静态变量/静态方法又称之为类变量 /类方法,它们存在于内存栈中,只有一份,可以通过类和对象直接访问

public class MyStatic {    public static String className = "MyStatic";    public static void getClassName() {        //当然你直接写className也能访问到,但前提是此函数里没有局部变量名覆盖静态变量名        System.out.println(MyStatic.className);    }        public static void main(String[] args) {        //类访问静态变量        System.out.println(MyStatic.className);        //对象访问静态变量        System.out.println((new Mystatic()).className);        //类访问静态方法        Mystatic.getClassName();        //对象访问静态方法        (new Mystatic()).getClassName();        //=========        (new Mystatic()).className = "new class name";        //=========        //类访问静态变量        System.out.println(MyStatic.className);        //对象访问静态变量        System.out.println((new Mystatic()).className);        //类访问静态方法        Mystatic.getClassName();        //对象访问静态方法        (new Mystatic()).getClassName();    }}

注意哟,java的静态变量并不禁止对象的访问,但PHP不同,PHP的静态方法是可以被对象调用,但类的静态变量只能被类的方法去访问,对象是不能直接访问的

class Mystatic {    public static $className = __CLASS__;    public static function getClassName() {        echo self::$className;    }}echo Mystatic::$className;Mystatic::getClassName();//but(new Mystatic())->className;//error 没有权限//but 下面是可以的(new Mystatic())->getClassName();//静态的只有一份,大家一起硬连接,同步修改Mystatic::$className = "new class Name";(new Mystatic())->getClassName();

所以PHP的对象如果要访问类的静态变量必须依靠接口,在类中写出访问静态变量的方法,而不能像Java一样直接使用.语法类和对象皆可访问

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