C# (C Sharp) Tutorial


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Introduction

If you're looking to learn C Sharp programming for beginners, one concept you'll want to get familiar with early on is LINQ—short for Language Integrated Query. LINQ is one of C#’s most powerful features, designed to make data querying easier and more readable. Whether you're working with arrays, collections, or databases, LINQ gives you a clean, expressive way to manage data.

This C# (C Sharp) tutorial will walk you through the basics of LINQ using practical, beginner-friendly examples. If you've already learned how to declare variables, write loops, and define methods in C#, you’re ready to dive into LINQ and take your coding skills to the next level.


What Is LINQ?

LINQ (Language Integrated Query) allows you to query data using C# syntax, instead of learning a separate language like SQL. With LINQ, you can query collections such as arrays, lists, dictionaries, XML files, and even databases (when used with Entity Framework).

Here's a simple example comparing traditional filtering with LINQ:

Without LINQ:

List<int> numbers = new List<int> { 1, 2, 3, 4, 5 };
List<int> evenNumbers = new List<int>();

foreach (int number in numbers)
{
    if (number % 2 == 0)
        evenNumbers.Add(number);
}

With LINQ:

List<int> numbers = new List<int> { 1, 2, 3, 4, 5 };
var evenNumbers = numbers.Where(n => n % 2 == 0).ToList();

Much cleaner, right? That’s the power of LINQ.


How LINQ Works

In LINQ, you query objects using methods and lambda expressions. It comes in two syntaxes:

  • Query Syntax (similar to SQL)
  • Method Syntax (more common in modern C#)

Both produce the same results, so choose the one you're most comfortable with.


Real-World LINQ Examples for Beginners

Let’s explore some common use cases to help you learn C Sharp programming for beginners more effectively through examples.


1. Filtering Data with Where

var names = new List<string> { "Anna", "Bob", "Charlie", "David" };
var shortNames = names.Where(name => name.Length <= 4);

foreach (var name in shortNames)
{
    Console.WriteLine(name); // Output: Anna, Bob
}

2. Selecting Specific Fields with Select

var numbers = new List<int> { 1, 2, 3, 4 };
var squares = numbers.Select(n => n * n);

foreach (var square in squares)
{
    Console.WriteLine(square); // Output: 1, 4, 9, 16
}

3. Sorting Data with OrderBy

var fruits = new List<string> { "Banana", "Apple", "Mango" };
var sortedFruits = fruits.OrderBy(f => f);

foreach (var fruit in sortedFruits)
{
    Console.WriteLine(fruit); // Output: Apple, Banana, Mango
}

4. Grouping Data with GroupBy

var scores = new List<int> { 90, 85, 70, 85, 60 };
var grouped = scores.GroupBy(score => score);

foreach (var group in grouped)
{
    Console.WriteLine($"Score: {group.Key}, Count: {group.Count()}");
}

5. Combining Conditions

var people = new List<string> { "Tom", "Jerry", "Alice", "Bob" };
var filtered = people
    .Where(p => p.StartsWith("A") || p.Length == 3)
    .OrderBy(p => p);

foreach (var person in filtered)
{
    Console.WriteLine(person); // Output: Alice, Bob, Tom
}

Tips for Learning LINQ Effectively

  • Start small: Practice with simple collections like List or List.
  • Use LINQPad: It’s a great tool for experimenting with LINQ queries in real-time.
  • Mix syntax styles: Try both query and method syntax to see which one fits your thinking.
  • Integrate with projects: Use LINQ in small personal apps like to-do lists or inventory managers.

Conclusion

This C# tutorial introduced you to the basics of LINQ—one of the most useful tools in any C# developer’s toolkit. Whether you're filtering names, selecting values, or grouping data, LINQ makes your code cleaner and more efficient.

As you continue to learn C Sharp programming for beginners, mastering LINQ will give you a strong edge. It enhances your ability to write code and work with real-world data.

Don’t just read about LINQ—try it out! Set up a small C# console project, load up a list of data, and start querying. That’s how real learning happens.