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Home Backend Development PHP Tutorial php的基础问题请教一下

php的基础问题请教一下

Jun 23, 2016 pm 01:40 PM

class Test1 {	static private $_name;}$_test1 = new Test1('张三');var_dump($_test1);
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页面输出的是:
object(Test1)#1 (0) { }
我实例化的时候还传递了参数,但是Test1的类中我没有写构造方法__construct(),为什么不会报错呢?



回复讨论(解决方案)

构造方法也不是必须的,你传参数进去,它不执行就是了

构造函数已知都在,你不定义只是那个函数为空。

构造方法也不是必须的,你传参数进去,它不执行就是了



基础不怎么牢,麻烦请举个简单的例子可以吗,谢谢!

class Test1 {    static private $_name;    public $_date;    public function __construct() {    	$this->_date = 123;    } }$_test1 = new Test1('张三');var_dump($_test1);
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我记得实例化类的时候,构造函数不是就执行了吗
为什么参数不对应啊?


class Test1 {
static private $_name;
}
并没有定义构造函数 __construct

class Test1 {    private static $_name;    public $_date;    public function __construct($name) {        $this->_date = 123;		self::$_name = $name;    }		function output(){		return self::$_name.' - '.$this->_date;	}} $_test1 = new Test1('张三');echo $_test1->output();
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