How the idea came to me:
When I first started programming back in my late twenties, I remember feeling both excited and overwhelmed by the sheer possibilities the world of code could offer. I’d just gotten my first taste of C#, and after mastering “Hello World!” I knew I needed to create something interactive and fun. That’s when I decided to build a “Guess the Number” game—a simple project that taught me a lot about variables, conditionals, loops, and even a bit of error handling. Today, I want to share that experience with you, along with a detailed walkthrough of how you can build your very own Guess the Number game in C#.
Why “Guess the Number”?
“Guess the Number” is a classic beginner project. It’s simple enough that you can complete it in a few hours, yet it’s complex enough to introduce several core programming concepts. When I built mine, I learned about:
- Variables and Data Types: How to store and manipulate numbers and text.
- User Input and Output: How to read what a user types into the console and display messages back to them.
- Control Flow: Using if/else statements to provide feedback (“Too high” or “Too low”) and loops to allow repeated guessing.
- Random Number Generation: How to generate a number that the user has to guess.
- Error Handling: Ensuring that the program doesn’t crash if the user enters invalid input.
This game is a small but excellent introduction to the art of programming because it gives you immediate feedback and a sense of accomplishment when the puzzle is solved.
Setting Up Your Environment
Before you start coding, make sure you have Visual Studio or Visual Studio Code installed on your Windows machine. I personally use Visual Studio Community Edition because it’s free and comes loaded with tools that make building C# applications a breeze.
Once your development environment is ready, create a new Console Application project. In Visual Studio, this is as simple as selecting “Create a new project” and choosing “Console App (.NET Core)” or “Console App (.NET Framework)” (I recommend .NET Core or .NET 5+ for new projects).
The Core Logic of the Game
At its heart, the Guess the Number game works as follows:
- Generate
a random number.
Using C#’s built-in Random class, the program picks a number between 1 and 100 (or any range you prefer). - Prompt
the user for a guess.
The program asks the user to input a number via the console. - Compare
the guess to the target number.
If the guess is too low, the program prints “Too low!” If it’s too high, it prints “Too high!” This is repeated until the user correctly guesses the number. - Display
the result.
Once the correct number is guessed, the game congratulates the player and tells them how many attempts it took.
Let’s now break down each of these steps as we write the code.
Writing the Code
Below is the complete code for our Guess the Number game. I’ve included comments in the code so you can follow along easily.
{
internal class Program
{
static void Main(string[] args)
{
// Create an instance of Random to generate a random number.
Random random = new Random();
// Generate a random number between 1 and 100 (inclusive).
int numberToGuess = random.Next(1, 101);
// Initialize variables to store the user's guess and the number of attempts.
int guess = 0;
int attempts = 0;
// Welcome message and instructions.
Console.WriteLine("Welcome to the Guess the Number Game!");
Console.WriteLine("I have chosen a number between 1 and 100. Can you guess it?");
// Main game loop: keep asking for guesses until the correct number is guessed.
while (guess != numberToGuess)
{
Console.Write("Enter your guess: ");
string input = Console.ReadLine();
// Try to convert the input into an integer.
if (int.TryParse(input, out guess))
{
attempts++; // Increase the attempt counter.
// Compare the user's guess to the target number.
if (guess < numberToGuess)
{
else if (guess > numberToGuess)
{
// If the guess equals the number, the loop will exit.
else
{
Explanation of the Code
Let’s go through the code step by step:
Namespace and Class Declaration:
We begin by creating a namespaceGuessTheNumberGameand a classProgramcontaining theMainmethod. In C#, theMainmethod is the entry point of the console application.Random Number Generation:
The line
Random random = new Random();
creates an instance of the Random class. Then,
int numberToGuess = random.Next(1, 101);
generates a random number between 1 and 100. Notice that the upper bound in the
Nextmethod is exclusive, so we pass 101 to include 100 as a possible value.User Input and Loop:
We declare a variableguessto store the user’s input, andattemptsto count how many tries the user makes. Thewhileloop keeps running untilguessequalsnumberToGuess.Input Validation:
Inside the loop, we prompt the user for a guess and read the input usingConsole.ReadLine(). Theint.TryParsemethod is used to safely convert the input string to an integer. If the conversion fails, we prompt the user again by printing an error message.Conditional Checks:
Depending on whether the guess is lower or higher than the number to guess, the program prints “Too low!” or “Too high!” This immediate feedback helps the user adjust their next guess.Ending the Game:
When the user finally guesses correctly, the loop exits, and the program congratulates the player while showing the number of attempts taken.Graceful Exit:
Finally, we wait for the user to press any key before closing the console window usingConsole.ReadKey(). This is especially useful when running the program outside of an IDE, so the window doesn’t disappear immediately.
Expanding on the Concepts
Now that you have the code in front of you, let’s discuss why each part is important and how this simple project can help you grasp more advanced programming ideas.
Variables and Data Types
In our program, we use several variables:
- numberToGuess (int): Stores the randomly generated number.
- guess (int): Holds the user’s guess.
- attempts (int): Counts how many times the user has attempted a guess.
These integer variables are a fundamental data type in C#. Understanding how to declare and use them is essential in almost every programming task.
Input and Output
The Console.WriteLine and Console.Write methods are used to output text to the console. Meanwhile, Console.ReadLine is used to capture input from the user. Mastering these methods is key to creating interactive console applications.
Control Flow: Loops and Conditionals
The game uses a while loop to continually prompt the user for guesses. Within that loop, we use if, else if, and else statements to compare the user’s guess with the generated number. This control flow structure is the backbone of decision-making in programming.
For example, the logic:
if (guess < numberToGuess)
{
else if (guess > numberToGuess)
{
ensures that the program responds appropriately based on the guess. This simple branching logic can be scaled up to much more complex programs as you gain more experience.
Error Handling
Notice how we use int.TryParse to convert the user’s input safely into an integer. If the conversion fails (i.e., the user enters something that isn’t a number), the program doesn’t crash; instead, it asks for valid input. This is a very basic form of error handling, but it’s a crucial concept as your programs grow more complex.
Random Number Generation
The Random class in C# is used here to create an unpredictable game. Every time the game is run, a different number is chosen. This not only makes the game fun and challenging but also introduces you to the concept of non-deterministic behavior in programs—an idea that is applicable in many fields, from gaming to simulations.
Looping for Repeated Actions
The game repeatedly asks the user for input until the correct number is guessed. This is a perfect example of using loops to handle repeated actions. As you progress in programming, you’ll find that loops are one of the most powerful tools in your arsenal, used in everything from processing lists of items to handling continuous data streams.
Making it More Interesting
Once you’re comfortable with this basic game, you can add additional features to make it even more interesting:
- Difficulty Levels: Allow the user to choose between easy, medium, and hard, each with a different range of numbers.
- Score Keeping: Track how many games the user has won and how many guesses it took on average.
- Replay Option: Ask the user if they want to play again after guessing the number.
- Hints: Provide more detailed hints based on how far off the guess is from the target number.
Here’s an example snippet for adding a replay feature:
bool playAgain = true;
while (playAgain)
{
// [Place the game logic here]
Console.WriteLine("Do you want to play again? (y/n)");
string response = Console.ReadLine().ToLower();
playAgain = response == "y" || response == "yes";
}
By integrating features like these, you deepen your understanding of program structure and user interaction.
My Personal Take on Learning Through Projects
I remember the first time I wrote a program that wasn’t just “Hello World!”—it felt like a breakthrough. There’s something incredibly satisfying about seeing your code interact with a real user, even if it’s just a simple guessing game. Each bug you fixed, each new feature you added, built up your confidence and taught you something new about programming logic and problem-solving.
At that point in my career, I was juggling a full-time job, personal projects, and the desire to learn new technologies. Building small projects like this gave me the necessary confidence and foundation to tackle bigger, more challenging applications later on. For anyone just starting out, I highly recommend choosing a project that excites you—even if it’s as simple as guessing a number. The lessons you learn from these projects are invaluable.
Tips for Beginners
- Start Small: Don’t jump straight into complex projects. Begin with something like this game to understand the basics.
- Experiment: Change the code, tweak the messages, or alter the number range. Experimentation is one of the best ways to learn.
- Debugging is Normal: Expect bugs. Learn to use the debugger in Visual Studio to inspect variable values and follow your program’s flow.
- Read Others’ Code: Look at open-source projects or sample code online. You’ll notice different styles and solutions that can help shape your own coding style.
- Ask Questions: Join communities like Stack Overflow or local coding meetups. As a 30-year-old who’s been through the ups and downs of learning to code, I can tell you that asking for help is part of the process.
- Practice Regularly: Even spending 30 minutes a day coding can add up over time. Consistency is key.
Remember, every expert was once a beginner. There’s no shortcut to learning programming—it’s all about practice, persistence, and a willingness to solve problems. So fire up your IDE, type in the code, and have fun guessing that number!
Happy coding, and I look forward to hearing about your programming adventures!
Our friends over at C-Sharp HUB on YouTube have covered writing a similar game code in their video tutorial check it out here :
