OOP – Inheritance (extends)
Name:
Date:
Class:
A
Quick Questions
Shade in the A or B circle for each question.
1. Does extends let a class inherit from another class?
2. Does super() call the parent class's constructor?
3. Is 'Extends' with a capital E valid JavaScript syntax?
4. Must 'super' be written in lowercase?
5. Is 'extend' (without an s) the correct keyword?
B
Match the Pairs
Draw a line connecting each item on the left to its match on the right.
| Left column | Right column | |
|---|---|---|
| 1class Dog extends Animal { ... } | AWrong - 'super' must be lowercase | |
| 2super(name); | Bextends | |
| 3Lets one class inherit properties and methods from another | CWrong - 'extends' must be lowercase | |
| 4Calls the parent class's constructor inside a child class | DCalls the parent class's constructor with name | |
| 5class Dog Extends Animal { ... } | EDeclares Dog as a subclass that inherits from Animal | |
| 6Super(name); | Fsuper() |
C
Definitions
extends
D
Fill in the Blanks
Complete each line of code by filling in the missing parts.
1.
class Dog _______ Animal {
2.
_____(name);
3.
class Cat _______ Animal {
4.
constructor(name) {
_____(name);
}
5.
class Puppy _______ Dog {
E
Spot the Error
Shade in the letter of the line that contains an error.
Question 1
A
Class Ant extends Animal {
B
constructor(name) {
C
super(name);
D
}
E
}
Question 2
A
clas Bee extends Animal {
B
constructor(name) {
C
super(name);
D
}
E
}
Question 3
A
let name = "Rex";
B
class Fox Extends Animal {
C
constructor(name) {
D
super(name);
E
}
F
}
Question 4
A
let name2 = "Tom";
B
class Owl extend Animal {
C
constructor(name) {
D
super(name);
E
}
F
}
Question 5
A
class Bear extends Animal {
B
constructor(name) {
C
Super(name);
D
}
E
}
Answer Key
OOP – Inheritance (extends)
Section A: Quick Questions
Q1
A — Yes
Q2
A — Yes
Q3
A — No
Q4
B — Yes
Q5
B — No
Section B: Match the Pairs
Q1
class Dog extends Animal { ... } → Declares Dog as a subclass that inherits from Animal
Q2
super(name); → Calls the parent class's constructor with name
Q3
Lets one class inherit properties and methods from another → extends
Q4
Calls the parent class's constructor inside a child class → super()
Q5
class Dog Extends Animal { ... } → Wrong - 'extends' must be lowercase
Q6
Super(name); → Wrong - 'super' must be lowercase
Section C: Definitions
Q1
extends — Lets a class inherit properties and methods from another class.Section D: Fill in the Blanks
Q1
class Dog extends Animal {Q2
super(name);Q3
class Cat extends Animal {Q4
constructor(name) {
super(name);
}Q5
class Puppy extends Dog {Section E: Spot the Error
Q1
A — 'class' must be lowercase - a capital C causes an error.
Q2
A — 'class' is misspelled as 'clas'.
Q3
B — 'extends' must be lowercase - a capital E causes an error.
Q4
B — 'extends' is misspelled as 'extend'.
Q5
C — 'super' must be lowercase - a capital S causes an error.