Extending Methods in WebForms Core

This content originally appeared on DEV Community and was authored by Elanat Framework

In this tutorial, we will explain how to extending methods in WebForms Core technology. This allows us to make your code cleaner, more maintainable, reusable, and more responsive to your application’s needs.

Here we are using the C# method extension feature; some programming languages may have the same feature as C# or may have other constructs for extending WebForms class methods.

Example 1: Dynamic Message Component

Controller

using CodeBehind;

public partial class AddMessageController : CodeBehindController
{
    public void PageLoad(HttpContext context)
    {
        WebForms form = new WebForms();

        form.Message("Welcome to WebForms Core!"); // Extension method

        Control(form);
    }
}

Extension Method

public static class WebFormsExtension
{
    public static void Message(this WebForms form, string text)
    {
        form.AddTag("<body>", "h3");
        form.SetBackgroundColor("<h3>-1", "lightgreen");
        form.SetText("<h3>-1", text);
        form.Delete("<h3>-1");
        form.AssignDelay(3);
    }
}

What Happens?

Injects an <h3> tag into the <body>.
Styles it with a light green background.
Displays the text, then auto-removes it after 3 seconds.

Example 2: Auto-Generated Table from a Class

Controller

using CodeBehind;

public partial class AppendFormController : CodeBehindController
{
    public void PageLoad(HttpContext context)
    {
        var frameworks = new List<BackendFramework>
        {
            new BackendFramework { Name = "CodeBehind", Owner = "Elanat", ReleasedYear = "2023" },
            new BackendFramework { Name = "Django", Owner = "Django Software Foundation", ReleasedYear = "2005" },
            new BackendFramework { Name = "Laravel", Owner = "Taylor Otwell", ReleasedYear = "2011" },
            new BackendFramework { Name = "Spring Boot", Owner = "Pivotal Software", ReleasedYear = "2014" },
            new BackendFramework { Name = "Express.js", Owner = "OpenJS Foundation", ReleasedYear = "2010" },
            new BackendFramework { Name = "Ruby on Rails", Owner = "David Heinemeier Hansson", ReleasedYear = "2005" },
            new BackendFramework { Name = "ASP.NET Core", Owner = "Microsoft", ReleasedYear = "2016" }
        };

        WebForms form = new WebForms();

        form.GenerateTable("TableBox", frameworks); // Extension method

        Control(form);
    }
}

Class

public class BackendFramework
{
    public string Name { get; set; }
    public string Owner { get; set; }
    public string ReleasedYear { get; set; }
}

Extension Method

public static class WebFormsExtension
{
    public static void GenerateTable<T>(this WebForms form, string inputPlace, IEnumerable<T> data)
    {
        form.AddTag(inputPlace, "table");
        form.AddStyle(inputPlace + "|<table>-1", "border-collapse: collapse; width: 100%;");
        form.AddTag(inputPlace + "|<table>-1", "thead");
        form.AddTag(inputPlace + "|<thead>", "tr");
        form.SetBackgroundColor(inputPlace + "|<tr>", "whitesmoke");

        // Create headers using class property names
        foreach (var prop in typeof(T).GetProperties())
        {
            form.AddTag(inputPlace + "|<tr>", "th");
            form.SetText(inputPlace + "|<th>-1", prop.Name);
            form.AddStyle(inputPlace + "|<th>-1", "border: 1px solid #ddd; padding: 8px;");
        }

        form.AddTag(inputPlace + "|<table>-1", "tbody");

        foreach (var item in data)
        {
            form.AddTag(inputPlace + "|<tbody>", "tr");

            foreach (var prop in typeof(T).GetProperties())
            {
                var value = prop.GetValue(item)?.ToString() ?? "";
                form.AddTag(inputPlace + "|<tr>-1", "td");
                form.SetText(inputPlace + "|<td>-1", value);
                form.AddStyle(inputPlace + "|<td>-1", "border: 1px solid #ddd; padding: 8px;");
            }
        }
    }
}

Key Features:

Dynamically generates headers using class property names.
Iterates through data to create table rows/cells.
Applies consistent styling via inline CSS.

The image below shows the result of the table in the example above.

Example 3: Reusable Form Input Component

Extension Method

public static class WebFormsExtension
{
    public static void AddInputField(this WebForms form, string inputPlace, string label, string inputName)
    {
        form.AddTag(inputPlace, "div");
        form.AddStyle(inputPlace + "|<div>-1", "margin-bottom: 12px;");

        form.AddTag(inputPlace + "|<div>-1", "label");
        form.SetText(inputPlace + "|<label>-1", label);
        form.AddStyle(inputPlace + "|<label>-1", "display: block; font-weight: bold;");

        form.AddTag(inputPlace + "|<div>-1", "input");
        form.SetAttribute(inputPlace + "|<input>-1", "name", inputName);
        form.AddStyle(inputPlace + "|<input>-1", "width: 100%; padding: 8px 0px;");
    }
}

Usage

form.AddInputField("FormContainer", "Username:", "username");
form.AddInputField("FormContainer", "Password:", "password");

Why Use Extension Methods?

Cleaner Code: Encapsulate complex UI logic into reusable methods.
Consistency: Enforce styling/behavior patterns across pages.
Maintainability: Update logic in one place (the extension class).
Readability: Method names describe intent (e.g., GenerateTable).

Conclusion

Extension methods unlock powerful ways to extend WebForms Core’s built-in classes. By creating reusable components like dynamic tables, auto-removing messages, or form generators, you reduce repetition and build more maintainable applications. Start small (e.g., a custom Alert() method), then expand your toolkit as patterns emerge in your projects.

Example 1: Dynamic Message Component

Example 2: Auto-Generated Table from a Class

Example 3: Reusable Form Input Component

Why Use Extension Methods?

Conclusion

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