Declaring global variables in Typescript - Mini Project: Build & Apply

Declaring Global Variables in TypeScript

📖 Scenario: You are building a simple TypeScript program that tracks the number of visitors to a website. You want to use a global variable to keep count so that it can be accessed and updated from different parts of your program.

🎯 Goal: Create and use a global variable in TypeScript to count website visitors.

📋 What You'll Learn

Declare a global variable called visitorCount with initial value 0.

Create a function called addVisitor that increases visitorCount by 1.

Call the addVisitor function three times.

Print the final value of visitorCount.

💡 Why This Matters

🌍 Real World

Global variables are useful when you want to keep track of information that many parts of your program need to access or update, like counting visitors on a website.

💼 Career

Understanding global variables helps you manage data that needs to be shared across different functions or modules in real-world TypeScript applications.

1

Declare the global variable

Declare a global variable called visitorCount and set it to 0.

Typescript

// Your code here

Need a hint?

Use the let keyword to declare a variable that can change later.

2

Create a function to add visitors

Create a function called addVisitor that increases the global variable visitorCount by 1.

Typescript

let visitorCount = 0;

// Your code here

Need a hint?

Inside the function, use visitorCount += 1 to add one to the count.

3

Call the function multiple times

Call the function addVisitor exactly three times to increase visitorCount.

Typescript

let visitorCount = 0;

function addVisitor() {
    visitorCount += 1;
}

// Your code here

Need a hint?

Call addVisitor() three times, each on its own line.

4

Print the final visitor count

Print the value of the global variable visitorCount using console.log.

Typescript

let visitorCount = 0;

function addVisitor() {
    visitorCount += 1;
}

addVisitor();
addVisitor();
addVisitor();

// Your code here

Need a hint?

Use console.log(visitorCount) to display the count.