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) pick one of two actions (c) draw a screen (d) repeat forever
-
2.🔀 What does this battery rule show?
let battery = 26;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
3.🔀 What does this PIN rule show?
let pin = "198";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
4.🔀 What does this PIN rule show?
let pin = "51750";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
5.🔀 What does this PIN rule show?
let pin = "879";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
6.🔀 What number does this shop app show?
let total = 230;
if (total > 500) {
total = total - 50;
}
show(total); -
7.🔀 What number does this shop app show?
let total = 780;
if (total > 500) {
total = total - 50;
}
show(total); - 8.🔀 When does the else part run? (a) when the test is false (b) when the test is true (c) always (d) never
- 9.🔀 In this course’s code, which sign tests “is equal to”? (a) = (b) === (c) => (d) !==
-
10.🔀 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 -
11.🔀 What does this battery rule show?
let battery = 36;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
12.🔀 What does this PIN rule show?
let pin = "9613";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
13.🔀 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 -
14.🔀 What does this sign-up rule show?
let age = 17;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Ask a parent (b) Welcome! -
15.🔀 Which badge does this quiz app show?
let marks = 84;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Gold (c) Bronze -
16.🔀 What does this PIN rule show?
let pin = "2981";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits - 17.🔀 What does >= mean? (a) greater than or equal (b) smaller or equal (c) not equal (d) less than
-
18.🔀 What does this sign-up rule show?
let age = 14;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Ask a parent (b) Welcome! -
19.🔀 Which badge does this quiz app show?
let marks = 53;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Gold (c) Bronze -
20.🔀 Which badge does this quiz app show?
let marks = 90;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Bronze (b) Silver (c) Gold -
21.🔀 Which badge does this quiz app show?
let marks = 88;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Bronze (b) Gold (c) Silver -
22.🔀 Which badge does this quiz app show?
let marks = 20;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Bronze (c) Gold -
23.🔀 What does this battery rule show?
let battery = 67;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
24.🔀 Which badge does this quiz app show?
let marks = 46;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Gold (c) Bronze -
25.🔀 What does this battery rule show?
let battery = 3;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
26.🔀 What does this PIN rule show?
let pin = "612";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
27.🔀 What does this sign-up rule show?
let age = 13;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Ask a parent (b) Welcome! -
28.🔀 What number does this shop app show?
let total = 490;
if (total > 500) {
total = total - 50;
}
show(total); -
29.🔀 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) Silver (b) Gold (c) Bronze -
30.🔀 Which badge does this quiz app show?
let marks = 44;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Bronze (c) Gold -
31.🔀 What does this PIN rule show?
let pin = "550";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
32.🔀 What does this battery rule show?
let battery = 4;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
33.🔀 What does this battery rule show?
let battery = 49;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
34.🔀 What does this battery rule show?
let battery = 27;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
35.🔀 What does this PIN rule show?
let pin = "8374";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
36.🔀 Which badge does this quiz app show?
let marks = 97;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Bronze (b) Gold (c) Silver -
37.🔀 What does this PIN rule show?
let pin = "605";
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 = "67277";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
39.🔀 What does this PIN rule show?
let pin = "9095";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
40.🔀 What does this PIN rule show?
let pin = "542";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved
Answer key
- pick one of two actions
- Battery OK
- Use 4 digits
- Use 4 digits
- Use 4 digits
- 230
- 730
- when the test is false
- ===
- Battery OK
- Battery OK
- PIN saved
- Ask a parent
- Welcome!
- Gold
- PIN saved
- greater than or equal
- Welcome!
- Silver
- Gold
- Gold
- Bronze
- Battery OK
- Bronze
- Low battery
- Use 4 digits
- Welcome!
- 490
- Silver
- Bronze
- Use 4 digits
- Low battery
- Battery OK
- Battery OK
- PIN saved
- Gold
- Use 4 digits
- Use 4 digits
- PIN saved
- Use 4 digits
Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students