Async and await keywords in C Sharp (C#) - Mini Project: Build & Apply

Async and await keywords

📖 Scenario: You are building a simple console app that fetches data from a server. To keep the app responsive, you will use async and await keywords to handle the data fetching without blocking the main thread.

🎯 Goal: Create an asynchronous method to simulate fetching data, then call it using await and display the result.

📋 What You'll Learn

Create an asynchronous method called FetchDataAsync that returns a Task<string>.

Inside FetchDataAsync, simulate a delay of 2 seconds using Task.Delay.

Return a string message from FetchDataAsync after the delay.

In the Main method, call FetchDataAsync using await and store the result in a variable called data.

Print the data variable to the console.

💡 Why This Matters

🌍 Real World

Many apps need to fetch data from the internet or perform long tasks without freezing the screen. Using <code>async</code> and <code>await</code> helps keep apps smooth and responsive.

💼 Career

Understanding asynchronous programming is essential for software developers working on web apps, desktop apps, or any program that handles input/output or network calls efficiently.

1

Create the asynchronous method

Create an asynchronous method called FetchDataAsync that returns Task<string>. Inside it, simulate a 2-second delay using await Task.Delay(2000). After the delay, return the string "Data fetched successfully".

C Sharp (C#)

using System;
using System.Threading.Tasks;

class Program
{
    static async Task Main()
    {
    }

    // Your code here
}

Need a hint?

Use async before the method return type and await Task.Delay(2000) to simulate waiting.

2

Call the asynchronous method with await

Inside the Main method, call FetchDataAsync using await and store the result in a variable called data.

C Sharp (C#)

using System;
using System.Threading.Tasks;

class Program
{
    static async Task Main()
    {
        // Your code here
    }

    static async Task FetchDataAsync()
    {
        await Task.Delay(2000);
        return "Data fetched successfully";
    }
}

Need a hint?

Use string data = await FetchDataAsync(); inside Main.

3

Print the fetched data

Add a Console.WriteLine statement inside the Main method to print the data variable.

C Sharp (C#)

using System;
using System.Threading.Tasks;

class Program
{
    static async Task Main()
    {
        string data = await FetchDataAsync();
        // Your code here
    }

    static async Task FetchDataAsync()
    {
        await Task.Delay(2000);
        return "Data fetched successfully";
    }
}

Need a hint?

Use Console.WriteLine(data); to show the result.

4

Run and see the output

Run the program and observe the output. It should print Data fetched successfully after a 2-second delay.

C Sharp (C#)

using System;
using System.Threading.Tasks;

class Program
{
    static async Task Main()
    {
        string data = await FetchDataAsync();
        Console.WriteLine(data);
    }

    static async Task FetchDataAsync()
    {
        await Task.Delay(2000);
        return "Data fetched successfully";
    }
}

// Run the program to see the output

Need a hint?

Wait 2 seconds, then see the message printed.