C# INTERMEDIATEChapter 4 · C# Intermediate

LINQ Query Expressions

LINQ (Language Integrated Query) allows you to query collections of data directly in C# using syntax similar to SQL, or using method chains.

Worked example

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

class Program {
    static void Main() {
        int[] scores = { 45, 78, 92, 60 };
        var highScores = scores.Where(s => s > 70).OrderBy(s => s);
    }
}

How it reads

scores.Where(s => s > 70) filters the array elements
OrderBy(s => s) sorts the elements in ascending order

Cloud tip: LINQ methods are extension methods on IEnumerable<T> and require the namespace System.Linq.

LINQ Query Expressions

How it reads

Check your understanding