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.

Zusammenfassend ist **Ihre Aufgabe**, die Lücken zu füllen, wo nötig, um Reflection zu implementieren. 

Die Aufgabe wird im folgenden Video erklärt:

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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>.  
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<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 diesem Kurs werden wir einige fortgeschrittene C#-Konzepte zusammen mit MAUI kennenlernen, einer Bibliothek für die Anwendungsentwicklung. Wir werden lernen, wie man interessante GUI-Anwendungen erstellt, die schnell und reaktionsfähig bleiben, indem wir Techniken wie Threading verwenden. Wir werden Anwendungen erstellen, die mit Benutzereingaben und APIs interagieren, und darüber hinaus werden wir einige wichtige C#-Konzepte wie Reflection und Generics behandeln. Dieser Kurs wird unsere Programmierfähigkeiten weiter verbessern und uns eine starke Grundlage geben, um in Richtung Webentwicklung voranzukommen.

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.

Aufgabe - Reflection