C# 中的 Chrome PDF 渲染引擎：HTML轉PDF

# Using Package Manager Console
Install-Package IronPdf

# Using .NET CLI
dotnet add package IronPdf

# Using PackageReference in your .csproj file
<PackageReference Include="IronPdf" Version="*" />

using IronPdf;

Imports IronPdf

using IronPdf;

// Create a renderer with custom options
var renderer = new ChromePdfRenderer();

// Configure rendering options
renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.CssMediaType.Screen;
renderer.RenderingOptions.PrintHtmlBackgrounds = true;
renderer.RenderingOptions.CreatePdfFormsFromHtml = true;

// Set paper size and margins
renderer.RenderingOptions.PaperSize = IronPdf.Rendering.PdfPaperSize.A4;
renderer.RenderingOptions.MarginTop = 25;
renderer.RenderingOptions.MarginBottom = 25;
renderer.RenderingOptions.MarginLeft = 20;
renderer.RenderingOptions.MarginRight = 20;

// Set HTTP credentials if needed for protected resources
renderer.RenderingOptions.HttpLoginCredentials = new IronPdf.HttpLoginCredentials()
{
    Username = "yourUsername",
    Password = "yourPassword"
};

// Render HTML to PDF
var pdf = renderer.RenderHtmlAsPdf("<h1>Professional Document</h1><p>Generated with IronPDF</p>");
pdf.SaveAs("ProfessionalDocument.pdf");

Imports IronPdf

' Create a renderer with custom options
Dim renderer As New ChromePdfRenderer()

' Configure rendering options
renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.CssMediaType.Screen
renderer.RenderingOptions.PrintHtmlBackgrounds = True
renderer.RenderingOptions.CreatePdfFormsFromHtml = True

' Set paper size and margins
renderer.RenderingOptions.PaperSize = IronPdf.Rendering.PdfPaperSize.A4
renderer.RenderingOptions.MarginTop = 25
renderer.RenderingOptions.MarginBottom = 25
renderer.RenderingOptions.MarginLeft = 20
renderer.RenderingOptions.MarginRight = 20

' Set HTTP credentials if needed for protected resources
renderer.RenderingOptions.HttpLoginCredentials = New IronPdf.HttpLoginCredentials() With {
    .Username = "yourUsername",
    .Password = "yourPassword"
}

' Render HTML to PDF
Dim pdf = renderer.RenderHtmlAsPdf("<h1>Professional Document</h1><p>Generated with IronPDF</p>")
pdf.SaveAs("ProfessionalDocument.pdf")

using IronPdf;
using System.IO;

// Create a Chrome PDF renderer
var renderer = new ChromePdfRenderer();

// Configure for pixel-perfect rendering
renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.CssMediaType.Print;
renderer.RenderingOptions.EnableJavaScript = true;
renderer.RenderingOptions.RenderDelay = 500; // Wait for JavaScript to execute

// Load HTML from file
string htmlContent = File.ReadAllText("template.html");

// Include base URL for relative assets
renderer.RenderingOptions.BaseUrl = new Uri("file:///C:/your-project/assets/").AbsoluteUri;

// Render the HTML to PDF
var pdf = renderer.RenderHtmlAsPdf(htmlContent);

// Add metadata
pdf.MetaData.Author = "Your Company";
pdf.MetaData.Title = "Pixel-Perfect Document";
pdf.MetaData.CreationDate = DateTime.Now;

// Save the PDF
pdf.SaveAs("PixelPerfect.pdf");

Imports IronPdf
Imports System.IO

' Create a Chrome PDF renderer
Dim renderer As New ChromePdfRenderer()

' Configure for pixel-perfect rendering
renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.CssMediaType.Print
renderer.RenderingOptions.EnableJavaScript = True
renderer.RenderingOptions.RenderDelay = 500 ' Wait for JavaScript to execute

' Load HTML from file
Dim htmlContent As String = File.ReadAllText("template.html")

' Include base URL for relative assets
renderer.RenderingOptions.BaseUrl = New Uri("file:///C:/your-project/assets/").AbsoluteUri

' Render the HTML to PDF
Dim pdf = renderer.RenderHtmlAsPdf(htmlContent)

' Add metadata
pdf.MetaData.Author = "Your Company"
pdf.MetaData.Title = "Pixel-Perfect Document"
pdf.MetaData.CreationDate = DateTime.Now

' Save the PDF
pdf.SaveAs("PixelPerfect.pdf")

using IronPdf;
using System.Threading.Tasks;
using System.Collections.Generic;
using System.Linq;

// Example of using async rendering for a single document
public async Task<byte[]> GeneratePdfAsync(string html)
{
    var renderer = new ChromePdfRenderer();
    var pdfDocument = await renderer.RenderHtmlAsPdfAsync(html);
    return pdfDocument.BinaryData;
}

// Example of batch processing with parallel execution
public async Task GenerateMultiplePdfsAsync(List<string> htmlDocuments)
{
    var renderer = new ChromePdfRenderer();

    // Process multiple documents in parallel
    var tasks = htmlDocuments.Select(async (html, index) =>
    {
        var pdf = await renderer.RenderHtmlAsPdfAsync(html);
        await pdf.SaveAsAsync($"Document_{index}.pdf");
    });

    await Task.WhenAll(tasks);
}

// Example using Parallel.ForEach for CPU-intensive batch processing
public void GeneratePdfsBatch(List<string> urls)
{
    Parallel.ForEach(urls, new ParallelOptions { MaxDegreeOfParallelism = 4 }, url =>
    {
        var renderer = new ChromePdfRenderer();
        var pdf = renderer.RenderUrlAsPdf(url);
        pdf.SaveAs($"{Path.GetFileNameWithoutExtension(url)}.pdf");
    });
}

Imports IronPdf
Imports System.Threading.Tasks
Imports System.Collections.Generic
Imports System.Linq
Imports System.IO
Imports System.Threading

' Example of using async rendering for a single document
Public Async Function GeneratePdfAsync(html As String) As Task(Of Byte())
    Dim renderer As New ChromePdfRenderer()
    Dim pdfDocument = Await renderer.RenderHtmlAsPdfAsync(html)
    Return pdfDocument.BinaryData
End Function

' Example of batch processing with parallel execution
Public Async Function GenerateMultiplePdfsAsync(htmlDocuments As List(Of String)) As Task
    Dim renderer As New ChromePdfRenderer()

    ' Process multiple documents in parallel
    Dim tasks = htmlDocuments.Select(Async Function(html, index)
                                         Dim pdf = Await renderer.RenderHtmlAsPdfAsync(html)
                                         Await pdf.SaveAsAsync($"Document_{index}.pdf")
                                     End Function)

    Await Task.WhenAll(tasks)
End Function

' Example using Parallel.ForEach for CPU-intensive batch processing
Public Sub GeneratePdfsBatch(urls As List(Of String))
    Parallel.ForEach(urls, New ParallelOptions With {.MaxDegreeOfParallelism = 4}, Sub(url)
                                                                                      Dim renderer As New ChromePdfRenderer()
                                                                                      Dim pdf = renderer.RenderUrlAsPdf(url)
                                                                                      pdf.SaveAs($"{Path.GetFileNameWithoutExtension(url)}.pdf")
                                                                                  End Sub)
End Sub