Easy C# Code Snippets

Explore these C# code examples that you can easily copy and use in your own projects.

Basic Hello World

using System;

class Program
{
    static void Main()
    {
        Console.WriteLine("Hello World!");
    }
}   
                

Simple For Loop

using System;

class Program
{
    static void Main()
    {
        for (int i = 0; i < 5; i++)
        {
            Console.WriteLine("Loop iteration: " + i);
        }
    }
}      
                

Basic Calculator

using System;

class Calculator
{
    static void Main()
    {
        Console.Write("Enter first number: ");
        double num1 = Convert.ToDouble(Console.ReadLine());

        Console.Write("Enter second number: ");
        double num2 = Convert.ToDouble(Console.ReadLine());

        Console.Write("Enter operator (+, -, *, /): ");
        char operation = Convert.ToChar(Console.ReadLine());

        double result = 0;
        switch (operation)
        {
            case '+':
                result = num1 + num2;
                break;
            case '-':
                result = num1 - num2;
                break;
            case '*':
                result = num1 * num2;
                break;
            case '/':
                result = num1 / num2;
                break;
            default:
                Console.WriteLine("Invalid operator");
                return;
        }

        Console.WriteLine("Result: " + result);
    }
} 
                    

Temperature Converter

using System;

class TemperatureConverter
{
    static void Main()
    {
        Console.Write("Enter temperature in Celsius: ");
        double celsius = Convert.ToDouble(Console.ReadLine());

        double fahrenheit = (celsius * 9 / 5) + 32;
        Console.WriteLine("Temperature in Fahrenheit: " + fahrenheit);
    }
}     
                    

Guess the Number Game

using System;

class GuessTheNumber
{
    static void Main()
    {
        Random random = new Random();
        int numberToGuess = random.Next(1, 101);
        int userGuess = 0;

        Console.WriteLine("Guess a number between 1 and 100.");

        while (userGuess != numberToGuess)
        {
            userGuess = Convert.ToInt32(Console.ReadLine());

            if (userGuess > numberToGuess)
            {
                Console.WriteLine("Too high, try again.");
            }
            else if (userGuess < numberToGuess)
            {
                Console.WriteLine("Too low, try again.");
            }
        }

        Console.WriteLine("You guessed it! The number was " + numberToGuess);
    }
}  
                    

Simple ATM Interface

using System;

class ATM
{
    static void Main()
    {
        int balance = 1000;
        int withdrawal;

        Console.WriteLine("Welcome to the ATM");
        Console.Write("Enter amount to withdraw: ");
        withdrawal = Convert.ToInt32(Console.ReadLine());

        if (withdrawal <= balance)
        {
            balance -= withdrawal;
            Console.WriteLine("Please collect your cash. Your new balance is: " + balance);
        }
        else
        {
            Console.WriteLine("Insufficient funds!");
        }
    }
}         
                    

Palindrome Checker

using System;

class PalindromeChecker
{
    static void Main()
    {
        Console.Write("Enter a string: ");
        string input = Console.ReadLine();

        string reversed = ReverseString(input);

        if (input.Equals(reversed, StringComparison.OrdinalIgnoreCase))
        {
            Console.WriteLine(input + " is a palindrome.");
        }
        else
        {
            Console.WriteLine(input + " is not a palindrome.");
        }
    }

    static string ReverseString(string s)
    {
        char[] array = s.ToCharArray();
        Array.Reverse(array);
        return new string(array);
    }
}
                    

Simple Interest Calculator

using System;

class InterestCalculator
{
    static void Main()
    {
        Console.Write("Enter principal amount: ");
        double principal = Convert.ToDouble(Console.ReadLine());

        Console.Write("Enter rate of interest (in %): ");
        double rate = Convert.ToDouble(Console.ReadLine());

        Console.Write("Enter time (in years): ");
        double time = Convert.ToDouble(Console.ReadLine());

        double interest = (principal * rate * time) / 100;
        Console.WriteLine("Simple Interest: " + interest);
    }
}
                    

Factorial Calculator

using System;

class FactorialCalculator {
    static void Main() {
        Console.Write("Enter a number: ");
        int number = Convert.ToInt32(Console.ReadLine());

        int factorial = 1;
        for (int i = 1; i <= number; i++) {
            factorial *= i;
        }

        Console.WriteLine($"Factorial of {number} is {factorial}");
    }
}
                    

Fibonacci Series Generator

using System;

class FibonacciSeries {
    static void Main() {
        Console.Write("Enter the number of terms: ");
        int terms = Convert.ToInt32(Console.ReadLine());

        int first = 0, second = 1, next;

        for (int i = 0; i < terms; i++) {
            if (i <= 1) {
                next = i;
            } else {
                next = first + second;
                first = second;
                second = next;
            }
            Console.Write($"{next} ");
        }
    }
} 
                    

Prime Number Checker

using System;

class PrimeNumberChecker {
    static void Main() {
        Console.Write("Enter a number: ");
        int number = Convert.ToInt32(Console.ReadLine());

        bool isPrime = true;

        if (number < 2) {
            isPrime = false;
        }

        for (int i = 2; i <= Math.Sqrt(number); i++) {
            if (number % i == 0) {
                isPrime = false;
                break;
            }
        }

        if (isPrime) {
            Console.WriteLine($"{number} is a prime number.");
        } else {
            Console.WriteLine($"{number} is not a prime number.");
        }
    }
}