LINQ Basics

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LINQ Basics

LINQ Basics

LINQ (Language Integrated Query) lets you filter, transform, and aggregate collections declaratively using methods like Where, Select, and OrderBy. It's part of System.Linq and works over any IEnumerable<T>. LINQ queries are typically chained together to express data pipelines in a single readable statement.

Note: LINQ methods are lazily evaluated — they don't run until you enumerate the result, e.g. with foreach or .ToList().

Example: LINQ Basics

markup

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main(string[] args)
    {
        List<int> numbers = new List<int> { 1, 2, 3, 4, 5, 6 };

        var evenSquares = numbers
            .Where(n => n % 2 == 0)
            .Select(n => n * n)
            .ToList();

        foreach (int n in evenSquares)
        {
            Console.WriteLine(n);
        }
    }
}

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LINQ Basics

LINQ Basics

Chapter Quiz — Complete all 7 topics to unlock

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