Rajeev Pentyala – Technical Blog on Power Platform, Azure and AI

I recently came across the IEnumerable Debugger Visualizer in Visual Studio, and it made debugging IEnumerable collections much easier.

I wanted to share this feature in this blog post and show how it works using a simple C# console application.

This feature is available starting from Visual Studio 2022 (version 17.2 Preview 2).

What is the IEnumerable Debugger Visualizer?

• In C#, IEnumerable<T> represents a collection that can be iterated.
• For example, IEnumerable<Car> can hold a list of Car objects, where each car has properties like Make, Model, Year, and `Color.

With the IEnumerable Debugger Visualizer, Visual Studio now lets you:

• View all records in a table-like view
• See the count and values clearly
• Filter data using expressions

Now that we understand what the IEnumerable Debugger Visualizer is, let’s see how it works in practice using a simple C# console application.

Using IEnumerable Debugger Visualizer:

Here is the simple console app I used for this demo. It generates a collection of cars and returns it as IEnumerable<Car>.

// See https://aka.ms/new-console-template for more information
Console.WriteLine("Hello, World!");

// Generate a collection of cars
var cars = GenerateCars(50);

Console.WriteLine("Generated Cars:\n");

foreach (var car in cars)
{
    Console.WriteLine($"{car.Year} {car.Make} {car.Model} ({car.Name}) - {car.Color}");
}

// Function to generate a collection of Car objects
static IEnumerable<Car> GenerateCars(int carCount)
{
    string[] names = { "Lightning", "Thunder", "Storm", "Blaze", "Rocket" };
    string[] colors = { "Red", "Blue", "Black", "White", "Silver" };
    string[] makes = { "Toyota", "Honda", "Ford", "Chevrolet", "BMW" };
    string[] models = { "Sedan", "SUV", "Coupe", "Truck", "Hatchback" };

    var random = new Random();
    var carList = new List<Car>();

    for (int i = 0; i < carCount; i++)
    {
        carList.Add(new Car
        {
            Name = names[random.Next(names.Length)],
            Color = colors[random.Next(colors.Length)],
            Make = makes[random.Next(makes.Length)],
            Model = models[random.Next(models.Length)],
            Year = random.Next(2015, 2025)
        });
    }

    return carList;
}

// Car class
class Car
{
    public string Name { get; set; }
    public string Color { get; set; }
    public string Model { get; set; }
    public string Make { get; set; }
    public int Year { get; set; }
}

• Place a breakpoint right after this line:

var cars = GenerateCars(50);

• Build and run the project
• When the debugger hits the breakpoint:
  • Hover over the cars variable
  • Click it to open the IEnumerable Visualizer

• Once the visualizer opens:
  • All car records are shown in a table
  • You can clearly see values like Make, Model, Year, and Color

Filtering Data Using Expressions:

• Click on the ‘Copilot’ icon highlighted below.

• Enter a natural language query, such as “Get the cars made in 2020”, and submit it.

• The visualizer automatically generates the corresponding expression and filters the data accordingly.

If you work with C# collections, IEnumerable Debugger Visualizer will quickly become part of your daily debugging workflow. If you haven’t tried it yet, open Visual Studio, hit a breakpoint, and give it a try.

🙂