App Dev Worksheet: If Else Rules
Developer's tip (Test, then choose): if (test) { A } else { B }: A runs when the test is true, B when it is false. else if: check from the top; the first true test wins and the rest are skipped. >= includes the number itself; > does not. === tests “is equal to”.
NameDateTime takenScore ___ / 40
- 1.🔀 What does if / else let an app do? (a) save a photo (b) draw a screen (c) pick one of two actions (d) repeat forever
-
2.🔀 What does this PIN rule show?
let pin = "2913";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
3.🔀 What does this sign-up rule show?
let age = 16;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Welcome! (b) Ask a parent -
4.🔀 Which badge does this quiz app show?
let marks = 36;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Gold (c) Bronze - 5.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) !== (c) === (d) =>
-
6.🔀 Which badge does this quiz app show?
let marks = 30;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Bronze (c) Gold - 7.🔀 When does the else part run? (a) when the test is true (b) always (c) never (d) when the test is false
-
8.🔀 Which badge does this quiz app show?
let marks = 45;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Gold (b) Silver (c) Bronze - 9.🔀 With if / else if / else, how many parts run? (a) only one (b) all of them (c) none (d) two
-
10.🔀 What does this sign-up rule show?
let age = 15;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Welcome! (b) Ask a parent -
11.🔀 What does this battery rule show?
let battery = 1;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
12.🔀 What number does this shop app show?
let total = 660;
if (total > 500) {
total = total - 50;
}
show(total); -
13.🔀 What does this battery rule show?
let battery = 60;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
14.🔀 What does this PIN rule show?
let pin = "23694";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
15.🔀 Which badge does this quiz app show?
let marks = 72;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Bronze (c) Gold -
16.🔀 What does this battery rule show?
let battery = 24;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
17.🔀 What does this sign-up rule show?
let age = 10;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Welcome! (b) Ask a parent -
18.🔀 Which badge does this quiz app show?
let marks = 61;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Gold (b) Bronze (c) Silver -
19.🔀 What does this battery rule show?
let battery = 77;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
20.🔀 What does this PIN rule show?
let pin = "78867";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
21.🔀 What does this PIN rule show?
let pin = "729";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
22.🔀 What does this PIN rule show?
let pin = "6939";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
23.🔀 What does this sign-up rule show?
let age = 14;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Welcome! (b) Ask a parent -
24.🔀 What does this PIN rule show?
let pin = "395";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
25.🔀 What does this sign-up rule show?
let age = 12;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Welcome! (b) Ask a parent -
26.🔀 What does this PIN rule show?
let pin = "7242";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
27.🔀 Which badge does this quiz app show?
let marks = 75;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Gold (b) Silver (c) Bronze -
28.🔀 What does this battery rule show?
let battery = 79;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
29.🔀 What does this battery rule show?
let battery = 83;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
30.🔀 What does this battery rule show?
let battery = 4;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
31.🔀 What number does this shop app show?
let total = 800;
if (total > 500) {
total = total - 50;
}
show(total); -
32.🔀 What number does this shop app show?
let total = 360;
if (total > 500) {
total = total - 50;
}
show(total); -
33.🔀 What does this battery rule show?
let battery = 81;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
34.🔀 Which badge does this quiz app show?
let marks = 67;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Bronze (c) Gold -
35.🔀 What does this PIN rule show?
let pin = "3379";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
36.🔀 What number does this shop app show?
let total = 460;
if (total > 500) {
total = total - 50;
}
show(total); -
37.🔀 What does this PIN rule show?
let pin = "60345";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
38.🔀 What does this PIN rule show?
let pin = "42901";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
39.🔀 What does this sign-up rule show?
let age = 17;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Welcome! (b) Ask a parent -
40.🔀 What does this battery rule show?
let battery = 93;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery
Answer key
- pick one of two actions
- PIN saved
- Welcome!
- Bronze
- ===
- Bronze
- when the test is false
- Bronze
- only one
- Welcome!
- Low battery
- 610
- Battery OK
- Use 4 digits
- Silver
- Battery OK
- Ask a parent
- Silver
- Battery OK
- Use 4 digits
- Use 4 digits
- PIN saved
- Welcome!
- Use 4 digits
- Ask a parent
- PIN saved
- Silver
- Battery OK
- Battery OK
- Low battery
- 750
- 360
- Battery OK
- Silver
- PIN saved
- 460
- Use 4 digits
- Use 4 digits
- Welcome!
- Battery OK
Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students