A simple program to print "Hello, World!".
using System;
namespace HelloWorld
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Hello, World!");
}
}
}
A basic calculator that can add, subtract, multiply, and divide two numbers.
using System;
namespace SimpleCalculator
{
class Program
{
static void Main(string[] args)
{
Console.Write("Enter first number: ");
double num1 = Convert.ToDouble(Console.ReadLine());
Console.Write("Enter second number: ");
double num2 = Convert.ToDouble(Console.ReadLine());
Console.WriteLine("Choose an operation: + - * /");
char operation = Console.ReadLine()[0];
double result = 0;
switch (operation)
{
case '+':
result = num1 + num2;
break;
case '-':
result = num1 - num2;
break;
case '*':
result = num1 * num2;
break;
case '/':
if (num2 != 0)
{
result = num1 / num2;
}
else
{
Console.WriteLine("Error: Division by zero.");
return;
}
break;
default:
Console.WriteLine("Invalid operation.");
return;
}
Console.WriteLine("The result is: " + result);
}
}
}
A program to find the largest number among three numbers.
using System;
namespace LargestNumber
{
class Program
{
static void Main(string[] args)
{
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 third number: ");
double num3 = Convert.ToDouble(Console.ReadLine());
double largest = num1;
if (num2 > largest)
{
largest = num2;
}
if (num3 > largest)
{
largest = num3;
}
Console.WriteLine("The largest number is: " + largest);
}
}
}
A program to check if a string is a palindrome.
using System;
namespace PalindromeChecker
{
class Program
{
static void Main(string[] args)
{
Console.Write("Enter a string: ");
string str = Console.ReadLine();
string reversedStr = new string(str.Reverse().ToArray());
if (str.Equals(reversedStr))
{
Console.WriteLine(str + " is a palindrome.");
}
else
{
Console.WriteLine(str + " is not a palindrome.");
}
}
}
}
A program to print the Fibonacci series up to a specified number of terms.
using System;
namespace FibonacciSeries
{
class Program
{
static void Main(string[] args)
{
Console.Write("Enter the number of terms: ");
int n = Convert.ToInt32(Console.ReadLine());
int firstTerm = 0, secondTerm = 1;
Console.Write("Fibonacci Series: " + firstTerm + ", " + secondTerm);
for (int i = 1; i <= n - 2; ++i)
{
int nextTerm = firstTerm + secondTerm;
Console.Write(", " + nextTerm);
firstTerm = secondTerm;
secondTerm = nextTerm;
}
}
}
}
A simple game where the user has to guess a randomly generated number within a certain range.
using System;
namespace NumberGuessingGame
{
class Program
{
static void Main(string[] args)
{
Random random = new Random();
int numberToGuess = random.Next(1, 101);
int numberOfTries = 0;
int guess;
bool win = false;
while (!win)
{
Console.Write("Enter your guess (1-100): ");
guess = Convert.ToInt32(Console.ReadLine());
numberOfTries++;
if (guess == numberToGuess)
{
win = true;
Console.WriteLine("Congratulations! You've guessed the number in " + numberOfTries + " tries.");
}
else if (guess < numberToGuess)
{
Console.WriteLine("Too low! Try again.");
}
else
{
Console.WriteLine("Too high! Try again.");
}
}
}
}
}
A program to check if a number is prime.
using System;
namespace PrimeNumberChecker
{
class Program
{
static void Main(string[] args)
{
Console.Write("Enter a number: ");
int number = Convert.ToInt32(Console.ReadLine());
bool isPrime = true;
if (number <= 1)
{
isPrime = false;
}
else
{
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.");
}
}
}
}
Create a system to manage employee details using classes and objects.
using System;
namespace EmployeeManagementSystem
{
class Employee
{
private string name;
private int id;
private double salary;
public Employee(string name, int id, double salary)
{
this.name = name;
this.id = id;
this.salary = salary;
}
public void DisplayEmployeeDetails()
{
Console.WriteLine("Employee ID: " + id);
Console.WriteLine("Employee Name: " + name);
Console.WriteLine("Employee Salary: " + salary);
}
}
class Program
{
static void Main(string[] args)
{
Employee emp1 = new Employee("John Doe", 1, 50000);
Employee emp2 = new Employee("Jane Smith", 2, 60000);
emp1.DisplayEmployeeDetails();
Console.WriteLine();
emp2.DisplayEmployeeDetails();
}
}
}
Create a simple banking system with classes for BankAccount and Customer.
using System;
namespace BankingSystem
{
class BankAccount
{
private int accountNumber;
private double balance;
public BankAccount(int accountNumber, double balance)
{
this.accountNumber = accountNumber;
this.balance = balance;
}
public void Deposit(double amount)
{
balance += amount;
Console.WriteLine("Deposited: " + amount);
}
public void Withdraw(double amount)
{
if (amount <= balance)
{
balance -= amount;
Console.WriteLine("Withdrew: " + amount);
}
else
{
Console.WriteLine("Insufficient balance!");
}
}
public void DisplayBalance()
{
Console.WriteLine("Account Number: " + accountNumber);
Console.WriteLine("Balance: " + balance);
}
}
class Customer
{
private string name;
private BankAccount account;
public Customer(string name, BankAccount account)
{
this.name = name;
this.account = account;
}
public void DisplayCustomerDetails()
{
Console.WriteLine("Customer Name: " + name);
account.DisplayBalance();
}
}
class Program
{
static void Main(string[] args)
{
BankAccount account1 = new BankAccount(12345, 1000.0);
Customer customer1 = new Customer("Alice", account1);
customer1.DisplayCustomerDetails();
Console.WriteLine();
account1.Deposit(500.0);
account1.Withdraw(300.0);
Console.WriteLine();
customer1.DisplayCustomerDetails();
}
}
}
Create a simple library management system using classes for Book and Library.
using System;
using System.Collections.Generic;
namespace LibraryManagementSystem
{
class Book
{
public string Title { get; set; }
public string Author { get; set; }
public int ID { get; set; }
public Book(int id, string title, string author)
{
ID = id;
Title = title;
Author = author;
}
public void DisplayBookInfo()
{
Console.WriteLine("ID: " + ID);
Console.WriteLine("Title: " + Title);
Console.WriteLine("Author: " + Author);
}
}
class Library
{
private List books = new List();
public void AddBook(Book book)
{
books.Add(book);
Console.WriteLine("Book added successfully.");
}
public void RemoveBook(int id)
{
books.RemoveAll(b => b.ID == id);
Console.WriteLine("Book removed successfully.");
}
public void DisplayAllBooks()
{
Console.WriteLine("Books in the library:");
foreach (var book in books)
{
book.DisplayBookInfo();
Console.WriteLine();
}
}
}
class Program
{
static void Main(string[] args)
{
Library library = new Library();
Book book1 = new Book(1, "C# Programming", "John Doe");
Book book2 = new Book(2, "Learn OOP", "Jane Smith");
library.AddBook(book1);
library.AddBook(book2);
library.DisplayAllBooks();
library.RemoveBook(1);
library.DisplayAllBooks();
}
}
}
Create a student management system using classes for Student and School.
using System;
using System.Collections.Generic;
namespace StudentManagementSystem
{
class Student
{
public string Name { get; set; }
public int ID { get; set; }
public double GPA { get; set; }
public Student(int id, string name, double gpa)
{
ID = id;
Name = name;
GPA = gpa;
}
public void DisplayStudentInfo()
{
Console.WriteLine("ID: " + ID);
Console.WriteLine("Name: " + Name);
Console.WriteLine("GPA: " + GPA);
}
}
class School
{
private List students = new List();
public void AddStudent(Student student)
{
students.Add(student);
Console.WriteLine("Student added successfully.");
}
public void RemoveStudent(int id)
{
students.RemoveAll(s => s.ID == id);
Console.WriteLine("Student removed successfully.");
}
public void DisplayAllStudents()
{
Console.WriteLine("Students in the school:");
foreach (var student in students)
{
student.DisplayStudentInfo();
Console.WriteLine();
}
}
}
class Program
{
static void Main(string[] args)
{
School school = new School();
Student student1 = new Student(1, "Alice Johnson", 3.5);
Student student2 = new Student(2, "Bob Brown", 3.8);
school.AddStudent(student1);
school.AddStudent(student2);
school.DisplayAllStudents();
school.RemoveStudent(1);
school.DisplayAllStudents();
}
}
}
Create an inventory management system using classes for Product and Inventory.
using System;
using System.Collections.Generic;
namespace InventoryManagementSystem
{
class Product
{
public string Name { get; set; }
public int ID { get; set; }
public double Price { get; set; }
public Product(int id, string name, double price)
{
ID = id;
Name = name;
Price = price;
}
public void DisplayProductInfo()
{
Console.WriteLine("ID: " + ID);
Console.WriteLine("Name: " + Name);
Console.WriteLine("Price: " + Price);
}
}
class Inventory
{
private List products = new List();
public void AddProduct(Product product)
{
products.Add(product);
Console.WriteLine("Product added successfully.");
}
public void RemoveProduct(int id)
{
products.RemoveAll(p => p.ID == id);
Console.WriteLine("Product removed successfully.");
}
public void DisplayAllProducts()
{
Console.WriteLine("Products in the inventory:");
foreach (var product in products)
{
product.DisplayProductInfo();
Console.WriteLine();
}
}
}
class Program
{
static void Main(string[] args)
{
Inventory inventory = new Inventory();
Product product1 = new Product(1, "Laptop", 999.99);
Product product2 = new Product(2, "Smartphone", 499.99);
inventory.AddProduct(product1);
inventory.AddProduct(product2);
inventory.DisplayAllProducts();
inventory.RemoveProduct(1);
inventory.DisplayAllProducts();
}
}
}
A program to perform division and handle exceptions.
using System;
namespace DivisionWithExceptionHandling
{
class Program
{
static void Main(string[] args)
{
Console.Write("Enter the numerator: ");
int numerator = Convert.ToInt32(Console.ReadLine());
Console.Write("Enter the denominator: ");
int denominator = Convert.ToInt32(Console.ReadLine());
try
{
int result = numerator / denominator;
Console.WriteLine("Result: " + result);
}
catch (DivideByZeroException e)
{
Console.WriteLine("Error: Division by zero is not allowed.");
}
A program to handle array index out of bounds exception.
using System;
namespace ArrayIndexOutOfBounds
{
class Program
{
static void Main(string[] args)
{
int[] numbers = { 1, 2, 3, 4, 5 };
try
{
Console.WriteLine("Enter an index to access the array: ");
int index = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("Value at index " + index + ": " + numbers[index]);
}
catch (IndexOutOfRangeException e)
{
Console.WriteLine("Error: " + e.Message);
}
}
}
}
A program to handle invalid cast exception.
using System;
namespace InvalidCastException
{
class Program
{
static void Main(string[] args)
{
object obj = "Hello";
try
{
int num = (int)obj;
Console.WriteLine("Value: " + num);
}
catch (InvalidCastException e)
{
Console.WriteLine("Error: " + e.Message);
}
}
}
}
A program to handle divide by zero exception and log the error.
using System;
using System.IO;
namespace DivideByZeroExceptionWithLogging
{
class Program
{
static void Main(string[] args)
{
Console.Write("Enter the numerator: ");
int numerator = Convert.ToInt32(Console.ReadLine());
Console.Write("Enter the denominator: ");
int denominator = Convert.ToInt32(Console.ReadLine());
try
{
int result = numerator / denominator;
Console.WriteLine("Result: " + result);
}
catch (DivideByZeroException e)
{
Console.WriteLine("Error: Division by zero is not allowed.");
File.WriteAllText("error_log.txt", e.ToString());
}
}
}
}
A program to validate user input and handle exceptions.
using System;
namespace UserInputValidation
{
class Program
{
static void Main(string[] args)
{
try
{
Console.Write("Enter an integer: ");
int number = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("You entered: " + number);
}
catch (FormatException e)
{
Console.WriteLine("Error: Invalid input format. Please enter an integer.");
}
catch (Exception e)
{
Console.WriteLine("Error: " + e.Message);
}
}
}
}
A program to read from and write to a text file.
using System;
using System.IO;
namespace FileIO
{
class Program
{
static void Main(string[] args)
{
string filePath = "example.txt";
// Write to file
string content = "Hello, this is a test file.";
File.WriteAllText(filePath, content);
// Read from file
string readFileContent = File.ReadAllText(filePath);
Console.WriteLine("File content: " + readFileContent);
}
}
}
A program to append text to an existing file.
using System;
using System.IO;
namespace AppendToFile
{
class Program
{
static void Main(string[] args)
{
string filePath = "example.txt";
Console.Write("Enter text to append: ");
string newText = Console.ReadLine();
File.AppendAllText(filePath, newText + Environment.NewLine);
Console.WriteLine("Text appended to file.");
}
}
}
A program to read a text file line by line.
using System;
using System.IO;
namespace ReadFileLineByLine
{
class Program
{
static void Main(string[] args)
{
string filePath = "example.txt";
if (File.Exists(filePath))
{
string[] lines = File.ReadAllLines(filePath);
foreach (string line in lines)
{
Console.WriteLine(line);
}
}
else
{
Console.WriteLine("File does not exist.");
}
}
}
}
A program to copy a file from one location to another.
using System;
using System.IO;
namespace CopyFile
{
class Program
{
static void Main(string[] args)
{
string sourceFilePath = "source