OOP – constructor Method
Name:
Date:
Class:
A
Quick Questions
Shade in the A or B circle for each question.
1. Does constructor() run automatically when a new instance is created?
2. Does 'this' refer to the instance being created inside constructor()?
3. Is 'Constructor' with a capital C valid JavaScript syntax?
4. Must 'new' be written in lowercase?
5. Can a constructor accept parameters like name or age?
B
Match the Pairs
Draw a line connecting each item on the left to its match on the right.
| Left column | Right column | |
|---|---|---|
| 1constructor(name) { this.name = name; } | Aconstructor(name) { ... } | |
| 2new Dog("Rex") | BWrong - 'constructor' must be lowercase | |
| 3Refers to the new object being created inside a constructor | CRuns automatically when a new Dog is created, setting name | |
| 4Runs automatically whenever a class is instantiated with new | DCreates a new Dog instance and calls its constructor | |
| 5Constructor(name) { this.name = name; } | Ethis | |
| 6let d = New Dog(5); | FWrong - 'new' must be lowercase |
C
Definitions
constructor
D
Fill in the Blanks
Complete each line of code by filling in the missing parts.
1.
___________(name) {
2.
this.name = ____;
3.
let myDog = new Dog("___");
4.
___________(color) {
5.
this.color = _____;
E
Spot the Error
Shade in the letter of the line that contains an error.
Question 1
A
Constructor(name) {
B
this.name = name;
C
}
Question 2
A
constructor(name) {
B
name = name;
C
}
Question 3
A
constructor(name) {
B
this.name = name;
C
]
Question 4
A
Constructor(age) {
B
this.age = age;
C
}
D
let d = new Dog(5);
Question 5
A
constructor(age) {
B
this.age = age;
C
}
D
let d = New Dog(5);
Answer Key
OOP – constructor Method
Section A: Quick Questions
Q1
A — Yes
Q2
B — Yes
Q3
A — No
Q4
A — Yes
Q5
B — Yes
Section B: Match the Pairs
Q1
constructor(name) { this.name = name; } → Runs automatically when a new Dog is created, setting name
Q2
new Dog("Rex") → Creates a new Dog instance and calls its constructor
Q3
Refers to the new object being created inside a constructor → this
Q4
Runs automatically whenever a class is instantiated with new → constructor(name) { ... }
Q5
Constructor(name) { this.name = name; } → Wrong - 'constructor' must be lowercase
Q6
let d = New Dog(5); → Wrong - 'new' must be lowercase
Section C: Definitions
Q1
constructor — A special method inside a class that runs automatically when a new instance is created.Section D: Fill in the Blanks
Q1
constructor(name) {Q2
this.name = name;Q3
let myDog = new Dog("Rex");Q4
constructor(color) {Q5
this.color = color;Section E: Spot the Error
Q1
A — 'constructor' must be lowercase - a capital C causes an error.
Q2
B — Missing 'this.' before name - it should be this.name.
Q3
C — The block must close with }, not ].
Q4
A — 'constructor' must be lowercase - a capital C causes an error.
Q5
D — 'new' must be lowercase - a capital N causes an error.