PHP · Theory

Inheritance

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Theory

58/352

Inheritance

Inheritance is a PHP idea you prove with class Student, not with a slogan.

Inheritance order — meaning → new Student('Asha', 72) → one limit. Dumping ten features helps nobody.

Inheritance exists so Dev can keep class Student correct in a small OOP file.

Use Inheritance when class Student must stay clear. If a simpler PHP step works, use that instead.

If class Student breaks under Inheritance, check public everything first.

Place Inheritance next to nearby PHP work — new Student('Asha', 72) is the link.

Viva for Inheritance — what it is → new Student('Asha', 72) → the mistake (public everything).

Exam tip

For Inheritance: definition + a small OOP file + one failure.

Example

<?php
// Inheritance
$scores = [80, 90, 70];
$avg = array_sum($scores) / count($scores);
echo "avg=" . number_format($avg, 1) . "\n";
foreach ($scores as $s) {
  if ($s >= 80) echo "high: $s\n";
}

Inheritance: scores array, print avg, then high marks. Say the output.

Short notes

DefInheritance — Dev uses it for class Student in a small OOP file.
RuleInheritance → new Student('Asha', 72).
RememberInheritance + the PHP runtime (a small OOP file).
UseInheritance in a small OOP file (class Student).
TrapInheritance — public everything.
ExInheritance → class Student.

PHP · Theory

Inheritance

← All stacks

Theory

58/352

Inheritance

Inheritance is a PHP idea you prove with class Student, not with a slogan.

Inheritance order — meaning → new Student('Asha', 72) → one limit. Dumping ten features helps nobody.

Inheritance exists so Dev can keep class Student correct in a small OOP file.

Use Inheritance when class Student must stay clear. If a simpler PHP step works, use that instead.

If class Student breaks under Inheritance, check public everything first.

Place Inheritance next to nearby PHP work — new Student('Asha', 72) is the link.

Viva for Inheritance — what it is → new Student('Asha', 72) → the mistake (public everything).

Exam tip

For Inheritance: definition + a small OOP file + one failure.

Example

<?php
// Inheritance
$scores = [80, 90, 70];
$avg = array_sum($scores) / count($scores);
echo "avg=" . number_format($avg, 1) . "\n";
foreach ($scores as $s) {
  if ($s >= 80) echo "high: $s\n";
}

Inheritance: scores array, print avg, then high marks. Say the output.

Short notes

DefInheritance — Dev uses it for class Student in a small OOP file.
RuleInheritance → new Student('Asha', 72).
RememberInheritance + the PHP runtime (a small OOP file).
UseInheritance in a small OOP file (class Student).
TrapInheritance — public everything.
ExInheritance → class Student.

Inheritance

Example

Short notes

Questions

Inheritance

Example

Short notes

Questions