Select clause projection in C Sharp (C#) - Mini Project: Build & Apply

Select Clause Projection in C#

📖 Scenario: You work in a bookstore and have a list of books with their details. You want to create a simple list showing only the book titles and their prices.

🎯 Goal: Build a C# program that uses LINQ's select clause to create a new list containing only the titles and prices of books.

📋 What You'll Learn

Create a list of books with title, author, and price

Create a variable to hold the minimum price filter

Use a LINQ query with select clause to project only title and price

Print the projected list showing title and price

💡 Why This Matters

🌍 Real World

Selecting and projecting data is common when working with collections, such as filtering products in a store or showing user details in an app.

💼 Career

Understanding LINQ and data projection is important for C# developers working on data processing, reporting, or UI display tasks.

1

Create the list of books

Create a list called books of type List<Book> with these exact entries: new Book("The Hobbit", "J.R.R. Tolkien", 15.99m), new Book("1984", "George Orwell", 12.50m), new Book("Clean Code", "Robert C. Martin", 33.99m). Also define the Book class with public properties Title, Author, and Price.

C Sharp (C#)

// Define the Book class and create the books list
// Your code here

Need a hint?

Define a class Book with properties for title, author, and price. Then create a List<Book> with the given books.

2

Add a minimum price filter

Create a decimal variable called minPrice and set it to 13.00m.

C Sharp (C#)

using System;
using System.Collections.Generic;

public class Book
{
    public string Title { get; set; }
    public string Author { get; set; }
    public decimal Price { get; set; }

    public Book(string title, string author, decimal price)
    {
        Title = title;
        Author = author;
        Price = price;
    }
}

class Program
{
    static void Main()
    {
        List books = new List
        {
            new Book("The Hobbit", "J.R.R. Tolkien", 15.99m),
            new Book("1984", "George Orwell", 12.50m),
            new Book("Clean Code", "Robert C. Martin", 33.99m)
        };
        // Create minPrice variable
        // Your code here
    }
}

Need a hint?

Just create a decimal variable named minPrice and assign it the value 13.00m.

3

Use LINQ select clause to project title and price

Write a LINQ query called selectedBooks that selects from books only those with Price greater than or equal to minPrice. Use the select clause to create an anonymous type with properties Title and Price.

C Sharp (C#)

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

public class Book
{
    public string Title { get; set; }
    public string Author { get; set; }
    public decimal Price { get; set; }

    public Book(string title, string author, decimal price)
    {
        Title = title;
        Author = author;
        Price = price;
    }
}

class Program
{
    static void Main()
    {
        List books = new List
        {
            new Book("The Hobbit", "J.R.R. Tolkien", 15.99m),
            new Book("1984", "George Orwell", 12.50m),
            new Book("Clean Code", "Robert C. Martin", 33.99m)
        };

        decimal minPrice = 13.00m;

        // Write LINQ query to select title and price
        // Your code here
    }
}

Need a hint?

Use a LINQ query with from, where, and select clauses. The select clause should create an anonymous type with Title and Price.

4

Print the selected book titles and prices

Use a foreach loop to print each book's Title and Price from selectedBooks. Format the output as: Title: [Title], Price: [Price].

C Sharp (C#)

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

public class Book
{
    public string Title { get; set; }
    public string Author { get; set; }
    public decimal Price { get; set; }

    public Book(string title, string author, decimal price)
    {
        Title = title;
        Author = author;
        Price = price;
    }
}

class Program
{
    static void Main()
    {
        List books = new List
        {
            new Book("The Hobbit", "J.R.R. Tolkien", 15.99m),
            new Book("1984", "George Orwell", 12.50m),
            new Book("Clean Code", "Robert C. Martin", 33.99m)
        };

        decimal minPrice = 13.00m;

        var selectedBooks = from book in books
                            where book.Price >= minPrice
                            select new { book.Title, book.Price };

        // Print the selected books
        // Your code here
    }
}

Need a hint?

Use a foreach loop to go through selectedBooks and print each book's title and price using Console.WriteLine with string interpolation.