小弟我觉得好迷糊

我觉得好迷糊啊

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?phpclass cA{    /**     * Test property for using direct default value     */    protected static $item = 'Foo';        /**     * Test property for using indirect default value     */    protected static $other = 'cA';        public static function method()    {        print self::$item."\r\n"; // It prints 'Foo' on everyway... :(        print self::$other."\r\n"; // We just think that, this one prints 'cA' only, but... :)    }        public static function setOther($val)    {        self::$other = $val; // Set a value in this scope.    }}class cB extends cA{    /**     * Test property with redefined default value     */    protected static $item = 'Bar';        public static function setOther($val)    {        self::$other = $val;    }}class cC extends cA{    /**     * Test property with redefined default value     */    protected static $item = 'Tango';        public static function method()    {        print self::$item."\r\n"; // It prints 'Foo' on everyway... :(        print self::$other."\r\n"; // We just think that, this one prints 'cA' only, but... :)    }        /**     * Now we drop redeclaring the setOther() method, use cA with 'self::' just for fun.     */}class cD extends cA{    /**     * Test property with redefined default value     */    protected static $item = 'Foxtrot';        /**     * Now we drop redeclaring all methods to complete this issue.     */}cB::setOther('cB'); // It's cB::method()!cB::method(); // It's cA::method()!cC::setOther('cC'); // It's cA::method()!cC::method(); // It's cC::method()!cD::setOther('cD'); // It's cA::method()!cD::method(); // It's cA::method()!/** * Results: -> * Foo * cB * Tango * cC * Foo * cD *  * What the hell?! :) */?>

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PHP code

class cA{    /**     * Test property for using direct default value     * 使用直接默认值测试属性     */    protected static $item = 'Foo';        /**     * Test property for using indirect default value     * 使用间接默认值测试属性     */    protected static $other = 'cA';        public static function method()    {        print __METHOD__ . ' ' . __CLASS__ . '::$item=' . self::$item."\r\n";        print __METHOD__ . ' ' . __CLASS__ . '::$otfer=' . self::$other."\r\n";    }        public static function setOther($val)    {        self::$other = $val; // Set a value in this scope.    }}class cB extends cA{    /**     * Test property with redefined default value     * 重新定义了默认值测试属性     */    protected static $item = 'Bar';        public static function setOther($val)    {        self::$other = $val;    }}class cC extends cA{    /**     * Test property with redefined default value     * 重新定义了默认值测试属性     */    protected static $item = 'Tango';        public static function method()    {        print __METHOD__ . ' ' . __CLASS__ . '::$item=' . self::$item."\r\n";        print __METHOD__ . ' ' . __CLASS__ . '::$otfer=' . self::$other."\r\n";    }        /**     * Now we drop redeclaring the setOther() method, use cA with 'self::' just for fun.     */}class cD extends cA{    /**     * Test property with redefined default value     * 重新定义了默认值测试属性     */    protected static $item = 'Foxtrot';        /**     * Now we drop redeclaring all methods to complete this issue.     * 现在，我们放弃重新声明的所有方法来完成这个问题     */}cB::setOther('cB'); // It's cB::method()!cB::method(); // It's cA::method()!cC::setOther('cC'); // It's cA::method()!cC::method(); // It's cC::method()!cD::setOther('cD'); // It's cA::method()!cD::method(); // It's cA::method()!<div class="clear">
                 
              
              
        
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