JavaScript Assignment
Learn how to assign and update values in variables
📝 Assignment Operators
Assignment operators are used to assign values to variables. The basic assignment operator is = (equals sign).
// Basic assignment
let name = "John";
let age = 25;
let isStudent = true;
console.log(name); // "John"
console.log(age); // 25
console.log(isStudent); // true
Console Output:
John 25 true
Types of Assignment Operators
Basic Assignment
Assigns a value to a variable
let x = 10;Addition Assignment
Adds and assigns the result
x += 5; // x = x + 5Subtraction Assignment
Subtracts and assigns the result
x -= 3; // x = x - 3Multiplication Assignment
Multiplies and assigns the result
x *= 2; // x = x * 2🔹 Assignment Operators in Action
Let's see how different assignment operators work:
let score = 100;
console.log("Initial score:", score);
// Addition assignment
score += 25; // Same as: score = score + 25
console.log("After += 25:", score);
// Subtraction assignment
score -= 10; // Same as: score = score - 10
console.log("After -= 10:", score);
// Multiplication assignment
score *= 2; // Same as: score = score * 2
console.log("After *= 2:", score);
// Division assignment
score /= 5; // Same as: score = score / 5
console.log("After /= 5:", score);Console Output:
Initial score: 100 After += 25: 125 After -= 10: 115 After *= 2: 230 After /= 5: 46
🔹 String Assignment
Assignment operators also work with strings:
let message = "Hello";
console.log("Initial:", message);
// String concatenation assignment
message += " World"; // Same as: message = message + " World"
console.log("After += ' World':", message);
message += "!";
console.log("After += '!':", message);
// Building a sentence
let greeting = "Good";
greeting += " morning";
greeting += ", ";
greeting += "everyone";
console.log("Final greeting:", greeting);Console Output:
Initial: Hello After += ' World': Hello World After += '!': Hello World! Final greeting: Good morning, everyone
🔹 Real-World Examples
Practical uses of assignment operators:
// Shopping cart total
let cartTotal = 0;
cartTotal += 29.99; // Add first item
cartTotal += 15.50; // Add second item
cartTotal += 8.25; // Add third item
console.log("Cart total: $" + cartTotal);
// Game score tracking
let playerScore = 0;
playerScore += 100; // Completed level
playerScore += 50; // Bonus points
playerScore -= 25; // Penalty
console.log("Player score:", playerScore);
// Building user profile
let userInfo = "Name: ";
userInfo += "Alice";
userInfo += ", Age: ";
userInfo += "28";
console.log(userInfo);Console Output:
Cart total: $53.74 Player score: 125 Name: Alice, Age: 28