新手请问下,类属性能初始化为一个其他类的实例对象吗
如果行的话,那语法是什么样的?
------解决方案--------------------
class A {}<br />class B {<br /> public $o;<br /> function __construct() {<br /> $this->o = new A;<br /> }<br />}<br />$p = new B;<br />print_r($p);
B Object<br />(<br /> [o] => A Object<br /> (<br /> )<br /><br />)<br /><br />
------解决方案--------------------
你的程序写错了。
1.第9行,你要显示$parameter属性,应是 echo $this->parameter; 而不是echo $parameter;
2.第15行 $test = new test("test"); 这个赋值并不会赋值到 private static $test,所以第20行的self::$test 是等于null
因此15行需要改为 self::$test = new test("test");
修改后的程序如下:
<br /><?php<br /> class test{<br /> private $parameter;<br /> public function __construct($parameter){<br /> $this->parameter=$parameter;<br /> echo "test类构造方法被调用<br/>";<br /> }<br /> public function getParameter(){<br /> echo $this->parameter; // 修改这里<br /> }<br /> }<br /> class test1{<br /> private static $test=null;<br /> public function __construct(){<br /> self::$test = new test("test"); // 修改这里<br /> echo "test1类构造方法被调用<br/>";<br /> }<br /> public static function show(){<br /> echo "show()方法被调用";<br /> self::$test->getParameter();//<br /> }<br /> }<br /> $test1 = new test1();<br /> test1::show();<br />?><br />
test类构造方法被调用
test1类构造方法被调用
show()方法被调用test
最后不得不说,自己有问题应该开贴,不应该在别人贴里面问。

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