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) repeat forever (b) pick one of two actions (c) save a photo (d) draw a screen
-
2.🔀 What does this PIN rule show?
let pin = "4314";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
3.🔀 What does this PIN rule show?
let pin = "785";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
4.🔀 What number does this shop app show?
let total = 440;
if (total > 500) {
total = total - 50;
}
show(total); - 5.🔀 When does the else part run? (a) always (b) when the test is false (c) never (d) when the test is true
-
6.🔀 What number does this shop app show?
let total = 230;
if (total > 500) {
total = total - 50;
}
show(total); -
7.🔀 What does this battery rule show?
let battery = 3;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
8.🔀 What does this PIN rule show?
let pin = "364";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
9.🔀 What number does this shop app show?
let total = 470;
if (total > 500) {
total = total - 50;
}
show(total); -
10.🔀 What number does this shop app show?
let total = 840;
if (total > 500) {
total = total - 50;
}
show(total); -
11.🔀 What does this PIN rule show?
let pin = "115";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
12.🔀 What does this PIN rule show?
let pin = "12484";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
13.🔀 Which badge does this quiz app show?
let marks = 92;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Gold (b) Bronze (c) Silver -
14.🔀 What does this sign-up rule show?
let age = 11;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Ask a parent (b) Welcome! -
15.🔀 What does this battery rule show?
let battery = 58;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
16.🔀 What does this battery rule show?
let battery = 15;
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 = 12;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Ask a parent (b) Welcome! -
18.🔀 Which badge does this quiz app show?
let marks = 81;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Bronze (c) Gold -
19.🔀 What number does this shop app show?
let total = 390;
if (total > 500) {
total = total - 50;
}
show(total); -
20.🔀 What does this battery rule show?
let battery = 52;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK - 21.🔀 What does >= mean? (a) smaller or equal (b) greater than or equal (c) not equal (d) less than
-
22.🔀 What number does this shop app show?
let total = 350;
if (total > 500) {
total = total - 50;
}
show(total); -
23.🔀 What does this battery rule show?
let battery = 26;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
24.🔀 What does this sign-up rule show?
let age = 9;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Ask a parent (b) Welcome! -
25.🔀 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) Gold (b) Silver (c) Bronze -
26.🔀 What does this battery rule show?
let battery = 64;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
27.🔀 What does this sign-up rule show?
let age = 8;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Ask a parent (b) Welcome! -
28.🔀 Which badge does this quiz app show?
let marks = 56;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Gold (b) Silver (c) Bronze -
29.🔀 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 -
30.🔀 Which badge does this quiz app show?
let marks = 71;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Gold (b) Bronze (c) Silver -
31.🔀 What does this battery rule show?
let battery = 81;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
32.🔀 Which badge does this quiz app show?
let marks = 42;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Gold (c) Bronze - 33.🔀 With if / else if / else, how many parts run? (a) two (b) only one (c) all of them (d) none
-
34.🔀 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! -
35.🔀 Which badge does this quiz app show?
let marks = 29;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Bronze (b) Gold (c) Silver -
36.🔀 What does this PIN rule show?
let pin = "86603";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
37.🔀 What does this PIN rule show?
let pin = "4497";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
38.🔀 What number does this shop app show?
let total = 430;
if (total > 500) {
total = total - 50;
}
show(total); -
39.🔀 What does this PIN rule show?
let pin = "192";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
40.🔀 What does this PIN rule show?
let pin = "72137";
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
- PIN saved
- Use 4 digits
- 440
- when the test is false
- 230
- Low battery
- Use 4 digits
- 470
- 790
- Use 4 digits
- Use 4 digits
- Gold
- Ask a parent
- Battery OK
- Low battery
- Ask a parent
- Gold
- 390
- Battery OK
- greater than or equal
- 350
- Battery OK
- Ask a parent
- Bronze
- Battery OK
- Ask a parent
- Silver
- Welcome!
- Silver
- Battery OK
- Bronze
- only one
- Welcome!
- Bronze
- Use 4 digits
- PIN saved
- 430
- Use 4 digits
- Use 4 digits
Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students