C# 泛型（對於開發者的運行原理）

public class Box<t>
{
    private T data;

    public Box(T data)
    {
        this.data = data;
    }

    public T Data
    {
        get { return data; }
    }
}

Public Class Box(Of T)
    Private data As T

    Public Sub New(data As T)
        Me.data = data
    End Sub

    Public ReadOnly Property Data As T
        Get
            Return data
        End Get
    End Property
End Class

Box<int> integerBox = new Box<int>(123);
Box<string> stringBox = new Box<string>("Hello");

Dim integerBox As New Box(Of Integer)(123)
Dim stringBox As New Box(Of String)("Hello")

public class Utility
{
    // Swaps two elements by reference using generics
    public static void Swap<t>(ref T lhs, ref T rhs)
    {
        T temp = lhs; // Store lhs in a temporary variable
        lhs = rhs;    // Assign rhs to lhs
        rhs = temp;   // Assign temp (original lhs) to rhs
    }
}

Public Class Utility
    ' Swaps two elements by reference using generics
    Public Shared Sub Swap(Of T)(ByRef lhs As T, ByRef rhs As T)
        Dim temp As T = lhs ' Store lhs in a temporary variable
        lhs = rhs ' Assign rhs to lhs
        rhs = temp ' Assign temp (original lhs) to rhs
    End Sub
End Class

int a = 1, b = 2;
Utility.Swap<int>(ref a, ref b);

string first = "world", second = "hello";
Utility.Swap(ref first, ref second);

Dim a As Integer = 1, b As Integer = 2
Utility.Swap(Of Integer)(a, b)

Dim first As String = "world", second As String = "hello"
Utility.Swap(first, second)

public interface IRepository<t>
{
    void Add(T item);
    T GetById(int id);
    IEnumerable<t> GetAll();
}

Public Interface IRepository(Of T)
    Sub Add(item As T)
    Function GetById(id As Integer) As T
    Function GetAll() As IEnumerable(Of T)
End Interface

public delegate void Action<t>(T item);

Public Delegate Sub Action(Of T)(item As T)

public class Result<t>
{
    public bool Success { get; private set; }
    public T Data { get; private set; }
    public string Message { get; private set; }

    public Result(bool success, T data, string message = "")
    {
        Success = success;
        Data = data;
        Message = message;
    }
}

Public Class Result(Of T)
    Public ReadOnly Property Success As Boolean
    Public ReadOnly Property Data As T
    Public ReadOnly Property Message As String

    Public Sub New(success As Boolean, data As T, Optional message As String = "")
        Me.Success = success
        Me.Data = data
        Me.Message = message
    End Sub
End Class

public class PdfOptions<t>
{
    public T Metadata { get; set; }
    public string HtmlContent { get; set; }
}

Public Class PdfOptions(Of T)
    Public Property Metadata As T
    Public Property HtmlContent As String
End Class

using IronPdf; // Make sure to include the necessary namespace for IronPDF

public static class PdfGenerator
{
    // Generates a PDF from provided HTML content and options
    public static void GeneratePdf<t>(PdfOptions<t> options)
    {
        // Initialize the IronPDF HtmlToPdf renderer
        var renderer = new ChromePdfRenderer();

        // Optional: Apply any renderer options here, for example, setting the paper size
        renderer.RenderingOptions.PaperSize = IronPdf.Rendering.PdfPaperSize.A4;

        // Generate the PDF from HTML content
        var pdfDocument = renderer.RenderHtmlAsPdf(options.HtmlContent);

        // Optional: Here, you can use options.Metadata in some way, depending on your generic type T
        // For simplicity, we're just printing the metadata to console if it's of type string
        if (options.Metadata is string metadataString)
        {
            Console.WriteLine($"Metadata: {metadataString}");
        }

        // Save the PDF to a file
        var fileName = $"GeneratedPdf_{DateTime.Now.Ticks}.pdf";
        pdfDocument.SaveAs(fileName);
        Console.WriteLine($"PDF generated and saved as {fileName}");
    }
}

Imports IronPdf ' Make sure to include the necessary namespace for IronPDF

Public Module PdfGenerator
    ' Generates a PDF from provided HTML content and options
    Public Sub GeneratePdf(Of T)(options As PdfOptions(Of T))
        ' Initialize the IronPDF HtmlToPdf renderer
        Dim renderer As New ChromePdfRenderer()

        ' Optional: Apply any renderer options here, for example, setting the paper size
        renderer.RenderingOptions.PaperSize = IronPdf.Rendering.PdfPaperSize.A4

        ' Generate the PDF from HTML content
        Dim pdfDocument = renderer.RenderHtmlAsPdf(options.HtmlContent)

        ' Optional: Here, you can use options.Metadata in some way, depending on your generic type T
        ' For simplicity, we're just printing the metadata to console if it's of type string
        If TypeOf options.Metadata Is String Then
            Dim metadataString As String = CType(options.Metadata, String)
            Console.WriteLine($"Metadata: {metadataString}")
        End If

        ' Save the PDF to a file
        Dim fileName As String = $"GeneratedPdf_{DateTime.Now.Ticks}.pdf"
        pdfDocument.SaveAs(fileName)
        Console.WriteLine($"PDF generated and saved as {fileName}")
    End Sub
End Module

class Program
{
    static void Main(string[] args)
    {
        // Set the license key for IronPDF if needed
        License.LicenseKey = "Your-License-Key-Here";

        // Create PDF options with HTML content and metadata
        var options = new PdfOptions<string>
        {
            HtmlContent = "<h1>Hello, World!</h1><p>This is a test PDF document generated from HTML.</p>",
            Metadata = "Test PDF Title"
        };

        // Generate the PDF using the specified options
        PdfGenerator.GeneratePdf(options);
    }
}

Friend Class Program
	Shared Sub Main(ByVal args() As String)
		' Set the license key for IronPDF if needed
		License.LicenseKey = "Your-License-Key-Here"

		' Create PDF options with HTML content and metadata
		Dim options = New PdfOptions(Of String) With {
			.HtmlContent = "<h1>Hello, World!</h1><p>This is a test PDF document generated from HTML.</p>",
			.Metadata = "Test PDF Title"
		}

		' Generate the PDF using the specified options
		PdfGenerator.GeneratePdf(options)
	End Sub
End Class