Abstract Classes in PHP
Abstract classes must have at least one abstract method. In php we can make class abstract using abstract keyword.
All Child classes implementing abstract class should give implementation of abstract methods which are in parent class. Abstract class can have abstract as well as non abstract methods
abstract class AbstractMainClass
{
abstract protected function fun1();
abstract protected function prefixValueFun($prefix);
// Common method
public function outPut() {
print $this->fun1() . "\n";
}
}
class NormalClass1 extends AbstractMainClass
{
protected function fun1() {
return "NormalClass1";
}
public function prefixValueFun($prefix) {
return "{$prefix}NormalClass1";
}
}
class NormalClass2 extends AbstractMainClass
{
public function fun1() {
return "NormalClass2";
}
public function prefixValueFun($prefix) {
return "{$prefix}NormalClass2";
}
}
$class1 = new NormalClass1;
$class1->outPut();
echo $class1->prefixValueFun('FOO_') ."\n";
$class2 = new NormalClass2;
$class2->outPut();
echo $class2->prefixValueFun('FOO_') ."\n";
Output
NormalClass1 FOO_NormalClass1 NormalClass2 FOO_NormalClass2
