我从Zend
PHP学习指南中得到这个问题,找不到正确的解释…
<?PHP
class Magic {
public $a = "A";
protected $b = array("a"=>"A","b"=>"B","c"=>"C");
protected $c = array(1,2,3);
public function __get($v) {
echo "$v,";
return $this->b[$v];
}
public function __set($var,$val) {
echo "$var: $val,";
$this->$var = $val;
}
}
$m = new Magic();
echo $m->a.",".$m->b.",".$m->c.",";
$m->c = "CC";
echo $m->a.",".$m->c;
?>
根据指南,解决方案应为“b,c,A,B,C,c：CC,b,C”.我不明白为什么 – 也许你这样做？我的意图是,首先调用$m-> a会导致结果“a”,但这显然是错误的…
由于__get()调用echo,所以在调用外部的echo之前,会输出一些数据.
用echo回到第一行,这是如何执行的：
$m->a "A" is concatenated "," "," is concatenated $m->b "b," is echoed,"B" is concatenated "," is concatenated $m->c "c,"C" is concatenated "m" "," is concatenated
此时,c已经被回显,现在显示值为A,Cm的字符串.