Comprehensive C# Tutorial

Introduction

C# is a modern, object-oriented programming language developed by Microsoft. It is used for a variety of applications, from web development to game development and enterprise-level applications. In this tutorial, we will cover the basics of C# programming, including syntax, data types, control structures, and object-oriented programming concepts.

Getting Started

To start programming in C#, you need a development environment. The most popular choice is Visual Studio, which provides a powerful IDE for C# development.

Download and install Visual Studio from here.

First C# Program

Let's start with a simple "Hello, World!" program to understand the structure of a C# application.

using System;

namespace HelloWorld
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello, World!");
        }
    }
}
                

Here, using System; imports the System namespace, which contains fundamental classes and base classes that define commonly-used data types, events, and event handlers, interfaces, attributes, and processing exceptions.

The namespace keyword is used to declare a scope that contains a set of related objects. HelloWorld is the name of the namespace.

The class keyword is used to define a class. Program is the name of the class.

The Main method is the entry point of a C# application. Console.WriteLine is used to print the specified message to the console.

Variables and Data Types

Variables are used to store data in a program. C# is a strongly-typed language, which means that every variable must have a type.

int age = 25;
double salary = 50000.75;
char grade = 'A';
string name = "John Doe";
bool isEmployed = true;
                

Here, we have declared variables of different data types:

• int: Integer data type
• double: Floating-point data type
• char: Character data type
• string: String data type
• bool: Boolean data type

Control Structures

Control structures are used to control the flow of execution in a program. C# supports various control structures, including conditional statements, loops, and switch statements.

Conditional Statements

int age = 18;

if (age >= 18)
{
    Console.WriteLine("You are an adult.");
}
else
{
    Console.WriteLine("You are not an adult.");
}
                

Loops

for (int i = 0; i < 5; i++)
{
    Console.WriteLine("Value of i: " + i);
}
                

Object-Oriented Programming

C# is an object-oriented programming language, which means it supports the concepts of classes and objects, inheritance, polymorphism, encapsulation, and abstraction.

Classes and Objects

class Person
{
    public string Name { get; set; }
    public int Age { get; set; }

    public void Introduce()
    {
        Console.WriteLine("Hello, my name is " + Name + " and I am " + Age + " years old.");
    }
}

Person person = new Person();
person.Name = "John Doe";
person.Age = 30;
person.Introduce();
                

Here, we have defined a Person class with two properties (Name and Age) and a method (Introduce). We then create an instance of the Person class and call the Introduce method.

Conclusion

In this tutorial, we have covered the basics of C# programming, including syntax, data types, control structures, and object-oriented programming concepts. With this foundation, you can start building more complex applications and explore advanced features of the C# language.