Php 获取子类实例

Php 获取子类实例,php,class,inheritance,instance,Php,Class,Inheritance,Instance,如何检查调用方法的子类以确定如何执行该方法 在Classes.php上: class Generic { public function foo() { // if its being called by Specific_1 subclass echo "bar"; // if its being called by Specific_2 subclass echo "zoo"; } } class Specific_1 extends Generic {} class Spec

如何检查调用方法的子类以确定如何执行该方法

在Classes.php上:

class Generic {

public function foo() {

// if its being called by Specific_1 subclass
echo "bar";

// if its being called by Specific_2 subclass
echo "zoo";
  }
}

class Specific_1 extends Generic {}

class Specific_2 extends Generic {}
关于脚本:

$spec1 = new Specific_1();
$spec2 = new Specific_2();

spec1->foo() // pretend to echo bar
spec2->foo() // pretend to echo zoo
Try关键字:


试用功能:

<?php
header('Content-Type: text/plain');

class Generic {
    public function foo() {
        if(is_a($this, 'Specific_1'))echo "bar";
        if(is_a($this, 'Specific_2'))echo "baz";
    }
}

class Specific_1 extends Generic {}
class Specific_2 extends Generic {}

$a = new Specific_1();
$a->foo();

echo PHP_EOL;

$b = new Specific_2();
$b->foo();
?>

另一种方法是:

p.S.:为什么不在每个类中重写方法呢

bar
zoo
<?php
header('Content-Type: text/plain');

class Generic {
    public function foo() {
        if(is_a($this, 'Specific_1'))echo "bar";
        if(is_a($this, 'Specific_2'))echo "baz";
    }
}

class Specific_1 extends Generic {}
class Specific_2 extends Generic {}

$a = new Specific_1();
$a->foo();

echo PHP_EOL;

$b = new Specific_2();
$b->foo();
?>
bar
baz
<?php
header('Content-Type: text/plain');

class Generic {
    public function foo() {
        switch($class = get_called_class()){
        case 'Specific_1':
            echo "bar";
            break;

        case 'Specific_2':
            echo "zoo";
            break;

        default:
            // default behaviour...
        }
    }
}

class Specific_1 extends Generic {}
class Specific_2 extends Generic {}

$a = new Specific_1();
$a->foo();

echo PHP_EOL;

$b = new Specific_2();
$b->foo();
?>
bar
zoo