如何使用ASP.NET Core和IronPDF構建中央化的PDF生成服務

dotnet new webapi -n PdfApiService
cd PdfApiService

dotnet add package IronPDF

public interface IPdfService
{
    byte[] GeneratePdfFromHtml(string htmlContent);
    byte[] GeneratePdfFromUrl(string url);
}

Public Interface IPdfService
    Function GeneratePdfFromHtml(htmlContent As String) As Byte()
    Function GeneratePdfFromUrl(url As String) As Byte()
End Interface

using IronPdf;
public class PdfService : IPdfService
{
    private readonly ChromePdfRenderer _renderer;
    public PdfService()
    {
        _renderer = new ChromePdfRenderer();
        // Configure rendering options for optimal PDF generation in .NET
        _renderer.RenderingOptions.MarginTop = 20;
        _renderer.RenderingOptions.MarginBottom = 20;
        _renderer.RenderingOptions.PrintHtmlBackgrounds = true;
    }
    public byte[] GeneratePdfFromHtml(string htmlContent)
    {
        // Generate PDF from HTML using the .NET PDF API
        var pdf = _renderer.RenderHtmlAsPdf(htmlContent);
        return pdf.BinaryData;
    }
    public byte[] GeneratePdfFromUrl(string url)
    {
        // Convert URL to PDF in the REST API
        var pdf = _renderer.RenderUrlAsPdf(url);
        return pdf.BinaryData;
    }
}

Imports IronPdf

Public Class PdfService
    Implements IPdfService

    Private ReadOnly _renderer As ChromePdfRenderer

    Public Sub New()
        _renderer = New ChromePdfRenderer()
        ' Configure rendering options for optimal PDF generation in .NET
        _renderer.RenderingOptions.MarginTop = 20
        _renderer.RenderingOptions.MarginBottom = 20
        _renderer.RenderingOptions.PrintHtmlBackgrounds = True
    End Sub

    Public Function GeneratePdfFromHtml(htmlContent As String) As Byte()
        ' Generate PDF from HTML using the .NET PDF API
        Dim pdf = _renderer.RenderHtmlAsPdf(htmlContent)
        Return pdf.BinaryData
    End Function

    Public Function GeneratePdfFromUrl(url As String) As Byte()
        ' Convert URL to PDF in the REST API
        Dim pdf = _renderer.RenderUrlAsPdf(url)
        Return pdf.BinaryData
    End Function

End Class

// Controllers/PdfController.cs
using Microsoft.AspNetCore.Mvc;
[ApiController]
[Route("api/[controller]")]
public class PdfController : ControllerBase
{
    private readonly IPdfService _pdfService;
    public PdfController(IPdfService pdfService)
    {
        _pdfService = pdfService;
    }
    [HttpPost("html-to-pdf")]
    public IActionResult ConvertHtmlToPdf([FromBody] HtmlRequest request)
    {
        try
        {
            var pdfBytes = _pdfService.GeneratePdfFromHtml(request.HtmlContent);
            // Return as downloadable file
            return File(pdfBytes, "application/pdf", "document.pdf");
        }
        catch (Exception ex)
        {
            return BadRequest($"Error generating PDF: {ex.Message}");
        }
    }
}

Imports Microsoft.AspNetCore.Mvc

<ApiController>
<Route("api/[controller]")>
Public Class PdfController
    Inherits ControllerBase

    Private ReadOnly _pdfService As IPdfService

    Public Sub New(pdfService As IPdfService)
        _pdfService = pdfService
    End Sub

    <HttpPost("html-to-pdf")>
    Public Function ConvertHtmlToPdf(<FromBody> request As HtmlRequest) As IActionResult
        Try
            Dim pdfBytes = _pdfService.GeneratePdfFromHtml(request.HtmlContent)
            ' Return as downloadable file
            Return File(pdfBytes, "application/pdf", "document.pdf")
        Catch ex As Exception
            Return BadRequest($"Error generating PDF: {ex.Message}")
        End Try
    End Function
End Class

// Models/HtmlRequest.cs
public class HtmlRequest
{
    public string HtmlContent { get; set; }
    public string FileName { get; set; } = "document.pdf";
}

' Models/HtmlRequest.vb
Public Class HtmlRequest
    Public Property HtmlContent As String
    Public Property FileName As String = "document.pdf"
End Class

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddControllers();
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
// Register PDF service
builder.Services.AddSingleton<IPdfService, PdfService>();
var app = builder.Build();
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}
app.UseHttpsRedirection();
app.MapControllers();
app.Run();

Imports Microsoft.AspNetCore.Builder
Imports Microsoft.Extensions.DependencyInjection

Dim builder = WebApplication.CreateBuilder(args)
builder.Services.AddControllers()
builder.Services.AddEndpointsApiExplorer()
builder.Services.AddSwaggerGen()
' Register PDF service
builder.Services.AddSingleton(Of IPdfService, PdfService)()
Dim app = builder.Build()
If app.Environment.IsDevelopment() Then
    app.UseSwagger()
    app.UseSwaggerUI()
End If
app.UseHttpsRedirection()
app.MapControllers()
app.Run()

public async Task<byte[]> GeneratePdfFromHtmlAsync(string htmlContent)
{
    return await Task.Run(() =>
    {
        var pdf = _renderer.RenderHtmlAsPdf(htmlContent);
        return pdf.BinaryData;
    });
}

Imports System.Threading.Tasks

Public Async Function GeneratePdfFromHtmlAsync(htmlContent As String) As Task(Of Byte())
    Return Await Task.Run(Function()
                              Dim pdf = _renderer.RenderHtmlAsPdf(htmlContent)
                              Return pdf.BinaryData
                          End Function)
End Function

_renderer.RenderingOptions.EnableJavaScript = false; // If JS not needed
_renderer.RenderingOptions.CssMediaType = PdfCssMediaType.Print;
_renderer.RenderingOptions.RenderDelay = 0; // Remove if no JS
_renderer.RenderingOptions.Timeout = 30; // Set reasonable timeout

public class Invoice
{
    public string InvoiceNumber { get; set; }
    public DateTime Date { get; set; }
    public string CustomerName { get; set; }
    public string CustomerAddress { get; set; }
    public List<InvoiceItem> Items { get; set; }
    public decimal Tax { get; set; }
}
public class InvoiceItem
{
    public string Description { get; set; }
    public int Quantity { get; set; }
    public decimal UnitPrice { get; set; }
    public decimal Total => Quantity * UnitPrice;
}

Public Class Invoice
    Public Property InvoiceNumber As String
    Public Property [Date] As DateTime
    Public Property CustomerName As String
    Public Property CustomerAddress As String
    Public Property Items As List(Of InvoiceItem)
    Public Property Tax As Decimal
End Class

Public Class InvoiceItem
    Public Property Description As String
    Public Property Quantity As Integer
    Public Property UnitPrice As Decimal
    Public ReadOnly Property Total As Decimal
        Get
            Return Quantity * UnitPrice
        End Get
    End Property
End Class

public class InvoiceService
{
    private readonly ChromePdfRenderer _renderer;
    public InvoiceService()
    {
        _renderer = new ChromePdfRenderer();
        _renderer.RenderingOptions.MarginTop = 10;
        _renderer.RenderingOptions.MarginBottom = 10;
        _renderer.RenderingOptions.PrintHtmlBackgrounds = true;
    }
    public byte[] GenerateInvoice(Invoice invoice)
    {
        var html = BuildInvoiceHtml(invoice);
        // Add footer with page numbers
        _renderer.RenderingOptions.HtmlFooter = new HtmlHeaderFooter
        {
            MaxHeight = 15,
            HtmlFragment = "<center><i>{page} of {total-pages}</i></center>",
            DrawDividerLine = true
        };
        var pdf = _renderer.RenderHtmlAsPdf(html);
        return pdf.BinaryData;
    }
    private string BuildInvoiceHtml(Invoice invoice)
    {
        var subtotal = invoice.Items.Sum(i => i.Total);
        var taxAmount = subtotal * (invoice.Tax / 100);
        var total = subtotal + taxAmount;
        var itemsHtml = string.Join("", invoice.Items.Select(item =>
            $@"<tr>
                <td>{item.Description}</td>
                <td class='text-center'>{item.Quantity}</td>
                <td class='text-right'>${item.UnitPrice:F2}</td>
                <td class='text-right'>${item.Total:F2}</td>
            </tr>"));
        return $@"
        <!DOCTYPE html>
        <html>
        <head>
            <style>
                body {{ font-family: Arial, sans-serif; }}
                .invoice-header {{
                    background-color: #f8f9fa;
                    padding: 20px;
                    margin-bottom: 20px;
                }}
                table {{
                    width: 100%;
                    border-collapse: collapse;
                }}
                th, td {{
                    padding: 10px;
                    border-bottom: 1px solid #ddd;
                }}
                th {{
                    background-color: #007bff;
                    color: white;
                }}
                .text-right {{ text-align: right; }}
                .text-center {{ text-align: center; }}
                .total-section {{
                    margin-top: 20px;
                    text-align: right;
                }}
            </style>
        </head>
        <body>
            <div class='invoice-header'>
                <h1>Invoice #{invoice.InvoiceNumber}</h1>
                <p>Date: {invoice.Date:yyyy-MM-dd}</p>
            </div>
            <div>
                <h3>Bill To:</h3>
                <p>{invoice.CustomerName}<br/>{invoice.CustomerAddress}</p>
            </div>
            <table>
                <thead>
                    <tr>
                        <th>Description</th>
                        <th>Quantity</th>
                        <th>Unit Price</th>
                        <th>Total</th>
                    </tr>
                </thead>
                <tbody>
                    {itemsHtml}
                </tbody>
            </table>
            <div class='total-section'>
                <p>Subtotal: ${subtotal:F2}</p>
                <p>Tax ({invoice.Tax}%): ${taxAmount:F2}</p>
                <h3>Total: ${total:F2}</h3>
            </div>
        </body>
        </html>";
    }
}

Imports System
Imports System.Linq

Public Class InvoiceService
    Private ReadOnly _renderer As ChromePdfRenderer

    Public Sub New()
        _renderer = New ChromePdfRenderer()
        _renderer.RenderingOptions.MarginTop = 10
        _renderer.RenderingOptions.MarginBottom = 10
        _renderer.RenderingOptions.PrintHtmlBackgrounds = True
    End Sub

    Public Function GenerateInvoice(invoice As Invoice) As Byte()
        Dim html = BuildInvoiceHtml(invoice)
        ' Add footer with page numbers
        _renderer.RenderingOptions.HtmlFooter = New HtmlHeaderFooter With {
            .MaxHeight = 15,
            .HtmlFragment = "<center><i>{page} of {total-pages}</i></center>",
            .DrawDividerLine = True
        }
        Dim pdf = _renderer.RenderHtmlAsPdf(html)
        Return pdf.BinaryData
    End Function

    Private Function BuildInvoiceHtml(invoice As Invoice) As String
        Dim subtotal = invoice.Items.Sum(Function(i) i.Total)
        Dim taxAmount = subtotal * (invoice.Tax / 100)
        Dim total = subtotal + taxAmount
        Dim itemsHtml = String.Join("", invoice.Items.Select(Function(item) _
            $"<tr>
                <td>{item.Description}</td>
                <td class='text-center'>{item.Quantity}</td>
                <td class='text-right'>${item.UnitPrice:F2}</td>
                <td class='text-right'>${item.Total:F2}</td>
            </tr>"))
        Return $"
        <!DOCTYPE html>
        <html>
        <head>
            <style>
                body {{ font-family: Arial, sans-serif; }}
                .invoice-header {{
                    background-color: #f8f9fa;
                    padding: 20px;
                    margin-bottom: 20px;
                }}
                table {{
                    width: 100%;
                    border-collapse: collapse;
                }}
                th, td {{
                    padding: 10px;
                    border-bottom: 1px solid #ddd;
                }}
                th {{
                    background-color: #007bff;
                    color: white;
                }}
                .text-right {{ text-align: right; }}
                .text-center {{ text-align: center; }}
                .total-section {{
                    margin-top: 20px;
                    text-align: right;
                }}
            </style>
        </head>
        <body>
            <div class='invoice-header'>
                <h1>Invoice #{invoice.InvoiceNumber}</h1>
                <p>Date: {invoice.Date:yyyy-MM-dd}</p>
            </div>
            <div>
                <h3>Bill To:</h3>
                <p>{invoice.CustomerName}<br/>{invoice.CustomerAddress}</p>
            </div>
            <table>
                <thead>
                    <tr>
                        <th>Description</th>
                        <th>Quantity</th>
                        <th>Unit Price</th>
                        <th>Total</th>
                    </tr>
                </thead>
                <tbody>
                    {itemsHtml}
                </tbody>
            </table>
            <div class='total-section'>
                <p>Subtotal: ${subtotal:F2}</p>
                <p>Tax ({invoice.Tax}%): ${taxAmount:F2}</p>
                <h3>Total: ${total:F2}</h3>
            </div>
        </body>
        </html>"
    End Function
End Class

[ApiController]
[Route("api/[controller]")]
public class InvoiceController : ControllerBase
{
    private readonly InvoiceService _invoiceService;
    public InvoiceController(InvoiceService invoiceService)
    {
        _invoiceService = invoiceService;
    }
    [HttpPost("generate")]
    public IActionResult GenerateInvoice([FromBody] Invoice invoice)
    {
        try
        {
            var pdfBytes = _invoiceService.GenerateInvoice(invoice);
            var fileName = $"Invoice_{invoice.InvoiceNumber}.pdf";
            return File(pdfBytes, "application/pdf", fileName);
        }
        catch (Exception ex)
        {
            return StatusCode(500, $"Error generating invoice: {ex.Message}");
        }
    }
}

Imports Microsoft.AspNetCore.Mvc

<ApiController>
<Route("api/[controller]")>
Public Class InvoiceController
    Inherits ControllerBase

    Private ReadOnly _invoiceService As InvoiceService

    Public Sub New(invoiceService As InvoiceService)
        _invoiceService = invoiceService
    End Sub

    <HttpPost("generate")>
    Public Function GenerateInvoice(<FromBody> invoice As Invoice) As IActionResult
        Try
            Dim pdfBytes = _invoiceService.GenerateInvoice(invoice)
            Dim fileName = $"Invoice_{invoice.InvoiceNumber}.pdf"
            Return File(pdfBytes, "application/pdf", fileName)
        Catch ex As Exception
            Return StatusCode(500, $"Error generating invoice: {ex.Message}")
        End Try
    End Function
End Class