Summary  
This chapter covers using reflection to inspect a class’s properties at runtime and implement code that dynamically generates UI entry fields, binds input values to object properties via PropertyInfo, and retrieves those values for display.  

General domain of usage  
Dynamic form generation and data binding in user interfaces

The base program is given on the <a 
href="https://github.com/Codefinity-Java/MAUIReflectionTask"
target="_blank"
style="color: #ff8a00; font-weight: 600; text-decoration: none; transition: 0.3s ease-in-out;"
onmouseover="this.style.color='#ff0000'"
onmouseout="this.style.color='#d27204'">Github Repository</a>. Clone the repository to begin solving the task.

In summary, **Your task** is to fill in the blanks where necessary to implement reflection. 

The task is explained in the following video:

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<div id="hint-block" class="block">
  <b>Hint 1:</b> The <code>GetProperties()</code> method of the <code>Type</code>code> class returns an array of all the public properties in a Type.<br>
  <b>Hint 2:</b> The <code>GetProperty(propertyName)</code>code> method of the <code>Type</code>code> class returns a reference to a single property which matches the <code>propertyName</code>.<br>
  <b>Hint 3:</b> The <code>SetValue(object, value)</code> method of the <code>PropertyInfo</code> class sets the property value of the <code>object</code> to <code>value</code>.  
</div>


<div id="solution-block" class="block">
  <pre><code class="language-csharp">
using System.Reflection;
using System.Security.AccessControl;

namespace ObjectManagerTask
{
    class Product
    {
        private static int Products = 0;

        private int ID { get; }
        public string Name { get; set; }
        public float Price { get; set; }
        public string Description { get; set; }

        public int Quantity { get; set; }

        public Product()
        {
            this.Name = "";
            this.Price = 0.0f;
            this.ID = Products++;
            this.Description = "";
        }
    }

    public partial class MainPage : ContentPage
    {
        List&lt;Product&gt; products = new List&lt;Product&gt;();
        public MainPage()
        {
            InitializeComponent();

            // Store the type of product class
            Type productType = typeof(Product);

            // Get all the properties of the Product class
            PropertyInfo[] properties = productType.GetProperties();

            // Loop through all the properties
            foreach (PropertyInfo property in properties)
            {
                Entry entryBox = new Entry();
                entryBox.Placeholder = property.Name;
                fields.Children.Add(entryBox);
            }

            createBtn.Clicked += CreateProduct;
        }

        void CreateProduct(object? sender, EventArgs e)
        {
            try
            {
                Product product = new Product();

                // Store the type of product class
                Type productType = product.GetType();

                foreach (Entry entryBox in fields.Children)
                {
                    // Get the property reference from the Product class, which has the same name as 'entryBox.Placeholder'.
                    // The exclamation mark ensures the compiler that the retrieved reference is not going to be null. 
                    // It is to suppress the warning.
                    PropertyInfo property = productType.GetProperty(entryBox.Placeholder)!;

                    object value = Convert.ChangeType(entryBox.Text, property.PropertyType);
                    property.SetValue(product, value);
                }

                products.Add(product);
            }
            catch
            {
                infoLabel.Text = $"ERROR: Invalid value in one of the fields.";
                return;
            }

            infoLabel.Text = $"Product {products.Count} created successfully.";

            ClearEntryBoxes();
            UpdateProductsList();
        }

        void UpdateProductsList()
        {
            productsList.Children.Clear();

            // Store the type of Product class
            Type productType = typeof(Product);

            foreach (Product product in products)
            {
                Label dataLabel = new Label();

                // Retrieve all the properties of productType
                PropertyInfo[] properties = productType.GetProperties();

                // Loop through all the properties
                foreach (PropertyInfo property in properties)
                {
                    // Get the value of 'property' from the 'product' object.
                    // The exclamation mark is to suppress the compiler warning since we know that the property exists,
                    // and it cannot return null.
                    object value = property.GetValue(product)!;

                    dataLabel.Text += $"{property.Name}: {value.ToString()}\t";
                }

                productsList.Children.Add(dataLabel);
            }
        }

        void ClearEntryBoxes()
        {
            foreach (Entry entryBox in fields.Children)
            {
                entryBox.Text = "";
            }
        }
    }
}
  </code></pre>
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In this course, we will learn about some advanced C# concepts along with MAUI, which is an application development library. We will learn how to create some interesting GUI applications while keeping them quick and responsive using techniques like Threading. We will make applications that will interact user input and APIs, and apart from that, we will cover some important C# concepts like Reflection and Generics. This course will further improve our programming skills and will give us a strong foundation to move forward towards Web Development.

In this section, we will learn what MAUI is, and how to set up a .NET MAUI application. We will also look at the structure of an MAUI application, and in the end, we will learn how to add some basic elements to our UI. This section will prepare us for the rest of the course where we will be working with more practical concepts.

In this section we will learn about delegates, events and data binding. Using this knowledge we will learn how to make interesting interactive GUI applications.

In this section, we will learn what Threading is and how to use it to keep our applications responsive, and run smoothly while performing resource intensive tasks. We will see how to differs from other similar concepts on C# and what are good practices when implementing Threading in our application. There will also be some interesting tasks to help us in understand this concept on a deeper level.

In this section, we will learn how to make more robust methods, classes and other objects which can work multiple types of input data types, by first learning about Generics and how to implement generic classes, then we will move on to Reflection and how to use reflection for further improving the capabilities of our programs.

Task - Reflection