C# Tutorial – Example Index

A collection of C# examples progressing from basic console I/O to advanced patterns such as delegates, threads, and LINQ. Each folder contains a self-contained project with its own README.md.

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📚 Examples

#	Topic	Key Concepts	Folder
001	External Argument	Main(string[] args), command-line arguments, for loop	001-ExternalArgument
002	Two Words	Basic class structure, System.Console.WriteLine	002-TwoWords
003	Min & Max Range of Data Types	Decimal, Single, Double min/max values, exponential format	003-MinimumRange
004	Operators	Arithmetic, logical, comparison operators, switch statement	004-Operators
005	Largest of Four Numbers	if comparisons, sequential max-finding	005-Four-Numbers
006	Five Numbers – Sum & Average	for loop, accumulator, integer vs. float division	006-Five-Numbers-Sum-and-Average
007	Two Numbers Triangle	Nested loops, triangle pattern, decrement	007-Two-Numbers-Triangle
008	C# Types	int, long, float, double, decimal, char, bool, string	008-CSharp-Types
009	Number to Words	while loop, modulo, string array, string concatenation	009-Num-to-Words
010	Explicit Type Casting	(short), (int) casts, data loss, GetType()	010-Cast-Int-Short-and-Float-Int
011	Class – Before .NET 5	Traditional class + Main boilerplate, using System	011-Class-Before-dotnet-5
012	Class – After .NET 5	Top-level statements, minimal syntax	012-Class-After-dotnet-5
013	Arrays Without Try-Catch	Arrays, IndexOutOfRangeException crash	013-Without-Try-Catch-Numbers-Array
014	Arrays With Try-Catch	try/catch, Exception.Message	014-Try-Catch-Numbers-Array
015	Try-Catch Custom Error Messages	Multiple catch blocks, specific exception types	015-Try-Catch-Numbers-Array-CustomErrorMessage
016	Namespaces – Calculator	namespace, multi-file project, using directives	016-Namespace-Calculator
017	Solution with Multiple Projects	.sln, dotnet new classlib, project references	017-Solution-and-projects
018	Delegates – Calculate	delegate type, delegate instance, method reference	018-Delegate-Calculate
019	Delegates – Print (Callback)	Lambda expressions, delegate as parameter, File.AppendAllText	019-Delegate-Print
020	Play Sound with NAudio	NuGet package, embedded resources, Mp3FileReader, WaveOutEvent	020-Play-Sound-Naudio
021	Observer Design Pattern	Observer pattern, interface, List<T>, polymorphism	021-Observer-Pattern
023	Threads	Thread, ThreadStart, Thread.Sleep, concurrency	023-Threads
024	LINQ Filter	System.Linq, query syntax, method/lambda syntax, Where()	024-LINQ-Filter

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🚀 Getting Started

Prerequisites

• .NET SDK (version 5 or later recommended)

Running an Example

Navigate to the inner project folder (the one containing the .csproj file) and run:

dotnet run

Or from the example's root folder:

dotnet run --project <ProjectFolderName>

Example:

cd 001-ExternalArgument
dotnet run --project ExternalArgumentApp -- Hello World

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📂 Repository Layout

CSharpTutorial/
├── README.md                        ← You are here
├── 001-ExternalArgument/
│   ├── README.md
│   └── ExternalArgumentApp/
├── 002-TwoWords/
│   ├── README.md
│   └── TwoWords/
... (one folder per example)
└── 024-LINQ-Filter/
    ├── README.md
    └── AppLinqFilter/

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🗂️ Topics by Category

Basics

• 001 – External Argument
• 002 – Two Words
• 008 – C# Types
• 011 – Class Before .NET 5
• 012 – Class After .NET 5

Control Flow & Loops

• 004 – Operators
• 005 – Largest of Four Numbers
• 006 – Five Numbers: Sum & Average
• 007 – Two Numbers Triangle
• 009 – Number to Words

Types & Conversions

• 003 – Min & Max Range
• 010 – Explicit Casting

Error Handling

• 013 – Arrays Without Try-Catch
• 014 – Arrays With Try-Catch
• 015 – Custom Error Messages

Project Organisation

• 016 – Namespaces
• 017 – Solution & Multiple Projects

Advanced Patterns

• 018 – Delegates: Calculate
• 019 – Delegates: Print / Callback
• 020 – Play Sound (NuGet / NAudio)
• 021 – Observer Pattern
• 023 – Threads
• 024 – LINQ Filter