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) pick one of two actions (b) repeat forever (c) save a photo (d) draw a screen
-
2.🔀 What does this battery rule show?
let battery = 45;
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 = "24488";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
4.🔀 Which badge does this quiz app show?
let marks = 49;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Gold (c) Bronze -
5.🔀 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 - 6.🔀 With if / else if / else, how many parts run? (a) all of them (b) none (c) two (d) only one
-
7.🔀 What does this PIN rule show?
let pin = "261";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved - 8.🔀 In this course’s code, which sign tests “is equal to”? (a) === (b) => (c) = (d) !==
-
9.🔀 What does this battery rule show?
let battery = 30;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
10.🔀 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! -
11.🔀 What number does this shop app show?
let total = 550;
if (total > 500) {
total = total - 50;
}
show(total); -
12.🔀 What number does this shop app show?
let total = 620;
if (total > 500) {
total = total - 50;
}
show(total); -
13.🔀 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) Bronze (b) Gold (c) Silver -
14.🔀 What does this sign-up rule show?
let age = 8;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Welcome! (b) Ask a parent -
15.🔀 What does this battery rule show?
let battery = 19;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
16.🔀 What number does this shop app show?
let total = 420;
if (total > 500) {
total = total - 50;
}
show(total); -
17.🔀 What does this battery rule show?
let battery = 57;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
18.🔀 What does this sign-up rule show?
let age = 9;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Welcome! (b) Ask a parent -
19.🔀 What does this PIN rule show?
let pin = "824";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits - 20.🔀 What does >= mean? (a) greater than or equal (b) smaller or equal (c) less than (d) not equal
-
21.🔀 What number does this shop app show?
let total = 670;
if (total > 500) {
total = total - 50;
}
show(total); -
22.🔀 What does this battery rule show?
let battery = 86;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery - 23.🔀 When does the else part run? (a) always (b) never (c) when the test is true (d) when the test is false
-
24.🔀 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 -
25.🔀 What does this PIN rule show?
let pin = "30684";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
26.🔀 What does this sign-up rule show?
let age = 15;
if (age >= 13) {
show("Welcome!");
} else {
show("Ask a parent");
} (a) Ask a parent (b) Welcome! -
27.🔀 Which badge does this quiz app show?
let marks = 43;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Gold (b) Bronze (c) Silver -
28.🔀 What does this battery rule show?
let battery = 62;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Low battery (b) Battery OK -
29.🔀 What number does this shop app show?
let total = 350;
if (total > 500) {
total = total - 50;
}
show(total); -
30.🔀 What does this PIN rule show?
let pin = "324";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) Use 4 digits (b) PIN saved -
31.🔀 What does this PIN rule show?
let pin = "847";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
32.🔀 What number does this shop app show?
let total = 520;
if (total > 500) {
total = total - 50;
}
show(total); -
33.🔀 What does this battery rule show?
let battery = 6;
if (battery < 20) {
show("Low battery");
} else {
show("Battery OK");
} (a) Battery OK (b) Low battery -
34.🔀 What does this PIN rule show?
let pin = "106";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
35.🔀 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 -
36.🔀 What does this PIN rule show?
let pin = "2573";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
37.🔀 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 -
38.🔀 What does this PIN rule show?
let pin = "41359";
if (pin.length === 4) {
show("PIN saved");
} else {
show("Use 4 digits");
} (a) PIN saved (b) Use 4 digits -
39.🔀 Which badge does this quiz app show?
let marks = 80;
if (marks >= 80) {
show("Gold");
} else if (marks >= 50) {
show("Silver");
} else {
show("Bronze");
} (a) Silver (b) Bronze (c) Gold -
40.🔀 What number does this shop app show?
let total = 770;
if (total > 500) {
total = total - 50;
}
show(total);
Answer key
- pick one of two actions
- Battery OK
- Use 4 digits
- Bronze
- Welcome!
- only one
- Use 4 digits
- ===
- Battery OK
- Ask a parent
- 500
- 570
- Silver
- Ask a parent
- Low battery
- 420
- Battery OK
- Ask a parent
- Use 4 digits
- greater than or equal
- 620
- Battery OK
- when the test is false
- Welcome!
- Use 4 digits
- Welcome!
- Bronze
- Battery OK
- 350
- Use 4 digits
- Use 4 digits
- 470
- Low battery
- Use 4 digits
- Ask a parent
- PIN saved
- Silver
- Use 4 digits
- Gold
- 720
Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students