PHP 5 adds a new final keyword. If a method in the parent class is declared final, the child class cannot override the method. If a class is declared final, it cannot be inherited.
Example #1 Final method example
class BaseClass
{
public function test(){
echo "BaseClass::test() called<br>";
}
final public function moreTesting(){
echo "BaseClass::moreTesting() called<br>";
}
}
class ChildClass extends BaseClass
{
public function moreTesting(){
echo "BaseClass::moreTeing called<br>";
}
}Example #2 Final class example
final class BaseClass{
public function test(){
echo "BaseClass::test() called\n";
}
//这里无论你是否将方法声明为final，都没有关系
final public function moreTesting(){
echo "BaseClass::moreTesting() called\n";
}
}
class ChildClass extends BaseClass{}
//产生Fatal Error:Class ChildClass may not inherit from final class (BaseClass)Note: Properties cannot be defined as final, only classes and methods can be defined as final.
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