Implementing the Builder Design Pattern Using .NET and C#

Simplifying Object Construction with the Builder Design Pattern in C#

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The builder pattern is a design pattern that allows you to create complex objects by specifying their components step by step.

Here is an example of how you might use the Builder Pattern class:

// Builder interface
public interface IHtmlBuilder
{
    void AddHeading(string heading);
    void AddParagraph(string paragraph);
    void AddLineBreak();
    string Build();
}

// Concrete builder
public class HtmlBuilder : IHtmlBuilder
{
    private readonly string _rootName;
    private readonly HtmlElement _root = new HtmlElement();
    public HtmlBuilder(string rootName)
    {
        _rootName = rootName;
        _root.Name = rootName;
    }

    public void AddHeading(string heading)
    {
        var element = new HtmlElement {Name = "h1", Text = heading};
        _root.Elements.Add(element);
    }
    public void AddParagraph(string paragraph)
    {
        var element = new HtmlElement {Name = "p", Text = paragraph};
        _root.Elements.Add(element);
    }
    public void AddLineBreak()
    {
        var element = new HtmlElement {Name = "br"};
        _root.Elements.Add(element);
    }
    public string Build()
    {
        return _root.ToString();
    }
}

// Element
public class HtmlElement
{
    public string Name, Text;
    public List<HtmlElement> Elements = new List<HtmlElement>();
    private const int _indentSize = 2;

    public override string ToString()
    {
        var sb = new StringBuilder();
        var i = new string(' ', _indentSize);
        sb.Append($"{i}<{Name}>\n");
        if (!string.IsNullOrWhiteSpace(Text))
        {
            sb.Append(new string(' ', _indentSize * 2));
            sb.Append(Text);
            sb.Append("\n");
        }

        foreach (var htmlElement in Elements)
        {
            sb.Append(htmlElement.ToString());
        }

        sb.Append($"{i}</{Name}>\n");
        return sb.ToString();
    }
}

// Client
class Program
{
    static void Main(string[] args)
    {
        var htmlBuilder = new HtmlBuilder("html");
        htmlBuilder.AddHeading("Hello World!");
        htmlBuilder.AddParagraph("This is a simple HTML document.");
        htmlBuilder.AddLineBreak();
        htmlBuilder.AddParagraph("It…