JavaScript Statements

1. Variable Declaration and Assignment Statements

Variable declaration statements are used to create variables, while assignment statements are used to assign values to variables.

Example:

// Variable Declaration
let name;

// Assignment Statement
name = "John";

2. Expression Statements

Expression statements are used to perform an action or calculation and can include variables, operators, and values.

Example:

let result = 5 * (10 + 3);
console.log(result); // Outputs: 65

3. Conditional Statements (if, else if, else)

Conditional statements allow you to execute different code based on specified conditions.

Example:

let age = 25;

if (age >= 18) {
console.log("You are an adult.");
} else {
console.log("You are a minor.");
}

4. Switch Statement

The switch statement allows you to choose one of many blocks of code to be executed.

Example:

let day = 3;
let dayName;

switch (day) {
case 1:
dayName = "Monday";
break;
case 2:
dayName = "Tuesday";
break;
// More cases...
default:
dayName = "Unknown";
}
console.log(dayName); // Outputs: Tuesday

5. Looping Statements (for, while, do-while)

Looping statements are used to repeat a block of code until a specified condition is met.

For Loop

for (let i = 0; i < 5; i++) {
console.log(i);
}
// Outputs: 0, 1, 2, 3, 4

While Loop

let count = 0;
while (count < 3) {
console.log(count);
count++;
}
// Outputs: 0, 1, 2

Do-While Loop

let num = 1;
do {
console.log(num);
num++;
} while (num <= 3);
// Outputs: 1, 2, 3

6. Break and Continue Statements

The break statement terminates the current loop, while the continue statement skips the current iteration and proceeds to the next one.

Example:

for (let i = 0; i < 5; i++) {
if (i === 3) {
break; // Exits the loop when i equals 3
}
console.log(i);
}
// Outputs: 0, 1, 2

for (let i = 0; i < 5; i++) {
if (i === 2) {
continue; // Skips iteration when i equals 2
}
console.log(i);
}
// Outputs: 0, 1, 3, 4

7. Function Declaration and Invocation Statements

Function declaration statements define reusable blocks of code, while function invocation statements execute those functions.

Example:

function greet(name) {
console.log(`Hello, ${name}!`);
}

greet("Alice"); // Outputs: Hello, Alice!

8. Try-Catch Statement

The try-catch statement is used for error handling to execute code and handle potential errors.

Example:

try {
// Code that may throw an error
let result = 10 / 0;
console.log(result);
} catch (error) {
console.log("An error occurred:", error.message);
}
// Outputs: An error occurred: Division by zero

9. Return Statement

The return statement is used inside functions to return a value and exit the function.

Example:

function add(a, b) {
return a + b;
}

let sum = add(5, 3);
console.log(sum); // Outputs: 8

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