C# LINQ (Language Integrated Query)

What is LINQ?

LINQ (Language Integrated Query) allows you to query and manipulate data in collections like lists and arrays.

It provides a clean and readable way to filter, sort, and transform data.

Filtering Data (Where)

The Where() method filters elements based on a condition.

Only elements that satisfy the condition are returned.

Transforming Data (Select)

The Select() method transforms each element into a new form.

This is useful for modifying data without changing the original collection.

Sorting Data

LINQ provides methods to sort data easily.

Use OrderBy() for ascending and OrderByDescending() for descending order.

First and Single

LINQ can retrieve single elements using methods like First().

These methods are useful when you only need one result.

Aggregation (Sum, Count, Average)

LINQ provides built-in methods to calculate values from collections.

These are useful for statistics and data analysis.

Lambda Expressions

LINQ uses lambda expressions to define conditions and transformations.

A lambda is a short way to write functions.

Real-World Example

LINQ is often used to process collections of objects.

Why LINQ is Important

LINQ is widely used in modern C# development.

• Used in databases (Entity Framework)
• Cleaner than loops
• Improves readability

Practice

Create a list of numbers and use LINQ to filter even numbers and print them.

Need Help?