Control Structures in JavaScript
Control structures allow developers to dictate the flow of program execution
based on conditions and logic. JavaScript supports conditional statements, loops,
and more.
1. Conditional Statements
if Statement
Executes a block of code if a specified condition evaluates to true.
let age = 18;
if (age >= 18) {
console.log("You are an adult.");
}
if...else Statement
Provides an alternative block of code if the condition is false.
let age = 16;
if (age >= 18) {
console.log("You are an adult.");
} else {
console.log("You are a minor.");
}
if...else if...else Statement
Used to test multiple conditions.
let score = 85;
if (score >= 90) {
console.log("Grade: A");
} else if (score >= 75) {
console.log("Grade: B");
} else {
, console.log("Grade: C");
}
switch Statement
Selects one of many blocks of code to execute.
let day = 3;
switch (day) {
case 1:
console.log("Monday");
break;
case 2:
console.log("Tuesday");
break;
case 3:
console.log("Wednesday");
break;
default:
console.log("Invalid day");
}
2. Loops
for Loop
Executes a block of code a specific number of times.
for (let i = 0; i < 5; i++) {
console.log(`Iteration ${i}`);
}
while Loop
Executes a block of code as long as a specified condition is true.
let count = 0;
while (count < 5) {
Control structures allow developers to dictate the flow of program execution
based on conditions and logic. JavaScript supports conditional statements, loops,
and more.
1. Conditional Statements
if Statement
Executes a block of code if a specified condition evaluates to true.
let age = 18;
if (age >= 18) {
console.log("You are an adult.");
}
if...else Statement
Provides an alternative block of code if the condition is false.
let age = 16;
if (age >= 18) {
console.log("You are an adult.");
} else {
console.log("You are a minor.");
}
if...else if...else Statement
Used to test multiple conditions.
let score = 85;
if (score >= 90) {
console.log("Grade: A");
} else if (score >= 75) {
console.log("Grade: B");
} else {
, console.log("Grade: C");
}
switch Statement
Selects one of many blocks of code to execute.
let day = 3;
switch (day) {
case 1:
console.log("Monday");
break;
case 2:
console.log("Tuesday");
break;
case 3:
console.log("Wednesday");
break;
default:
console.log("Invalid day");
}
2. Loops
for Loop
Executes a block of code a specific number of times.
for (let i = 0; i < 5; i++) {
console.log(`Iteration ${i}`);
}
while Loop
Executes a block of code as long as a specified condition is true.
let count = 0;
while (count < 5) {
