C# PDF库

HTML到PDF

using IronPdf;

// Disable local disk access or cross-origin requests
Installation.EnableWebSecurity = true;

// Instantiate Renderer
var renderer = new ChromePdfRenderer();

// Create a PDF from a HTML string using C#
var pdf = renderer.RenderHtmlAsPdf("<h1>Hello World</h1>");

// Export to a file or Stream
pdf.SaveAs("output.pdf");

// Advanced Example with HTML Assets
// Load external html assets: Images, CSS and JavaScript.
// An optional BasePath 'C:\site\assets\' is set as the file location to load assets from
var myAdvancedPdf = renderer.RenderHtmlAsPdf("<img src='icons/iron.png'>", @"C:\site\assets\");
myAdvancedPdf.SaveAs("html-with-assets.pdf");

using IronPdf;

// Disable local disk access or cross-origin requests
Installation.EnableWebSecurity = true;

// Instantiate Renderer
var renderer = new ChromePdfRenderer();

// Create a PDF from a HTML string using C#
var pdf = renderer.RenderHtmlAsPdf("<h1>Hello World</h1>");

// Export to a file or Stream
pdf.SaveAs("output.pdf");

// Advanced Example with HTML Assets
// Load external html assets: Images, CSS and JavaScript.
// An optional BasePath 'C:\site\assets\' is set as the file location to load assets from
var myAdvancedPdf = renderer.RenderHtmlAsPdf("<img src='icons/iron.png'>", @"C:\site\assets\");
myAdvancedPdf.SaveAs("html-with-assets.pdf");

PM >Install-Package IronPdf

Install-Package IronPdf

视频

如何使用C#将RTF转换为PDF

Curtis Chau

Updated: 2026年7月19日

为什么要从 NReco PDF 生成器迁移到 IronPDF?

NReco PDF 生成器的关键安全问题

NReco PDF Generator 包装了 wkhtmltopdf 二进制文件，继承了其已知的安全漏洞。 wkhtmltopdf 项目的最后一个稳定版本是 0.12.6 (2020年6月)，其上游仓库于 2023年1月2日归档，因此不会有任何补丁发布：

CVE-2020-21365： 目录遍历/ Crafted HTML 的本地文件读取 (同源策略弱点)
CVE-2022-35583: 通过在 0.12.6 中注入的<iframe>进行服务器端请求伪造 (SSRF) (CVSS 9.8)

NReco PDF 生成器的其他限制

大规模许可摩擦： 对于非SaaS的单服务器生产部署免费； SaaS、多服务器或再分发场景需要从nrecosite.com购买199美元的企业源代码包。
弃用的渲染引擎： WebKit Qt (约2012年) 仅支持有限的CSS3/JS：
- 无 CSS 网格或 Flexbox
- 无现代 JavaScript（ES6+）
- 网页字体支持不佳
- 无 CSS 变量或自定义属性
外部二进制依赖: 需要根据平台管理 wkhtmltopdf 二进制文件 (wkhtmltopdf.exe, wkhtmltox.dll)。
维护停滞： NReco.PdfGenerator 1.2.1 于2023年1月8日发布，自此后在nuget.org上未再有任何发布；底层 wkhtmltopdf 引擎不再更新。

5.**异步支持有限：**同步 API 会阻塞 Web 应用程序中的线程。

NReco PDF 生成器与IronPDF的比较

方面	NReco PDF 生成器	IronPDF
渲染引擎	WebKit Qt (2012)	Chromium （当前）
安全性	多个未修补的 CVEs (例如 CVE-2020-21365, CVE-2022-35583)；引擎于2023年1月2日归档	主动安全更新
CSS 支持	CSS2.1, 有限 CSS3	完全 CSS3、网格、Flexbox
JavaScript	基本 ES5	完整的 ES6+、async/await
依赖关系	外部 wkhtmltopdf 二进制文件	自成一体
异步支持	仅同步	完整的Async/Await
网络字体	有限的	完整的谷歌字体，@font-face
许可	非SaaS单服务器免费； SaaS/多服务器199美元企业包	透明的商业定价
免费级别	非SaaS单服务器许可证下免费	试用不需要水印

开始之前

前提条件

.NET 环境： .NET Framework 4.6.2+ 或 .NET Core 3.1+ / .NET 5/6/7/8/9+
**NuGet 访问权限：**能够安装 NuGet 包
**IronPDF 许可证：**请从ironpdf.com获取您的许可证密钥。

NuGet 软件包变更

# Remove NReco.PdfGenerator
dotnet remove package NReco.PdfGenerator

# Install IronPDF
dotnet add package IronPdf

# Remove NReco.PdfGenerator
dotnet remove package NReco.PdfGenerator

# Install IronPDF
dotnet add package IronPdf

SHELL

同时从您的部署中删除 wkhtmltopdf 二进制文件：

从项目中删除 wkhtmltopdf.exe, wkhtmltox.dll
删除任何 wkhtmltopdf 安装脚本
删除特定平台的二进制文件夹

许可配置

// Add at application startup (Program.cs or Startup.cs)
IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

// Add at application startup (Program.cs or Startup.cs)
IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

' Add at application startup (Program.vb or Startup.vb)
IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY"

' Add at application startup (Program.vb or Startup.vb)
IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY"

确定 NReco PDF 生成器的用途

# Find all NReco.PdfGenerator references
grep -r "NReco.PdfGenerator\|HtmlToPdfConverter\|GeneratePdf" --include="*.cs" .

# Find all NReco.PdfGenerator references
grep -r "NReco.PdfGenerator\|HtmlToPdfConverter\|GeneratePdf" --include="*.cs" .

SHELL

完整的 API 参考

核心类映射

NReco PDF 生成器	IronPDF
`HtmlToPdfConverter`	`ChromePdfRenderer`
`PageMargins`	个别边距属性
`PageOrientation`	`PdfPaperOrientation`
`PageSize`	`PdfPaperSize`

渲染方法映射

NReco PDF 生成器	IronPDF
`GeneratePdf(html)`	`RenderHtmlAsPdf(html)`
`GeneratePdfFromFile(url, output)`	`RenderUrlAsPdf(url)`
`GeneratePdfFromFile(htmlPath, output)`	`RenderHtmlFileAsPdf(path)`
（不支持异步）	`RenderHtmlAsPdfAsync(html)`
（不支持异步）	`RenderUrlAsPdfAsync(url)`

页面配置映射

NReco PDF 生成器	IronPDF
`PageWidth = 210`	`RenderingOptions.PaperSize = PdfPaperSize.A4`
`PageHeight = 297`	`RenderingOptions.SetCustomPaperSizeinMilimeters(w, h)`
`Orientation = PageOrientation.Landscape`	`RenderingOptions.PaperOrientation = PdfPaperOrientation.Landscape`
`Size = PageSize.A4`	`RenderingOptions.PaperSize = PdfPaperSize.A4`

边距映射

NReco PDF 生成器	IronPDF
`Margins.Top = 10`	`RenderingOptions.MarginTop = 10`
`Margins.Bottom = 10`	`RenderingOptions.MarginBottom = 10`
`Margins.Left = 10`	`RenderingOptions.MarginLeft = 10`
`Margins.Right = 10`	`RenderingOptions.MarginRight = 10`
`new PageMargins { ... }`	个别属性

页眉/页脚占位符映射

NReco PDF 生成器 (wkhtmltopdf)	IronPDF
`[page]`	`{page}`
`[topage]`	`{total-pages}`
`[date]`	`{date}`
`[time]`	`{time}`
`[title]`	`{html-title}`

输出处理映射

NReco PDF 生成器	IronPDF
`byte[] pdfBytes = GeneratePdf(html)`	`PdfDocument pdf = RenderHtmlAsPdf(html)`
`File.WriteAllBytes(path, bytes)`	`pdf.SaveAs(path)`
`return pdfBytes`	`return pdf.BinaryData`
`new MemoryStream(pdfBytes)`	`new MemoryStream(pdf.BinaryData)`

代码迁移示例

示例 1：将基本 HTML 转换为 PDF.

之前（NReco PDF 生成器）：

// NuGet: Install-Package NReco.PdfGenerator
using NReco.PdfGenerator;
using System.IO;

class Program
{
    static void Main()
    {
        var htmlToPdf = new HtmlToPdfConverter();
        var htmlContent = "<html><body><h1>Hello World</h1><p>This is a PDF document.</p></body></html>";
        var pdfBytes = htmlToPdf.GeneratePdf(htmlContent);
        File.WriteAllBytes("output.pdf", pdfBytes);
    }
}

// NuGet: Install-Package NReco.PdfGenerator
using NReco.PdfGenerator;
using System.IO;

class Program
{
    static void Main()
    {
        var htmlToPdf = new HtmlToPdfConverter();
        var htmlContent = "<html><body><h1>Hello World</h1><p>This is a PDF document.</p></body></html>";
        var pdfBytes = htmlToPdf.GeneratePdf(htmlContent);
        File.WriteAllBytes("output.pdf", pdfBytes);
    }
}

Imports NReco.PdfGenerator
Imports System.IO

Class Program
    Shared Sub Main()
        Dim htmlToPdf = New HtmlToPdfConverter()
        Dim htmlContent = "<html><body><h1>Hello World</h1><p>This is a PDF document.</p></body></html>"
        Dim pdfBytes = htmlToPdf.GeneratePdf(htmlContent)
        File.WriteAllBytes("output.pdf", pdfBytes)
    End Sub
End Class

Imports NReco.PdfGenerator
Imports System.IO

Class Program
    Shared Sub Main()
        Dim htmlToPdf = New HtmlToPdfConverter()
        Dim htmlContent = "<html><body><h1>Hello World</h1><p>This is a PDF document.</p></body></html>"
        Dim pdfBytes = htmlToPdf.GeneratePdf(htmlContent)
        File.WriteAllBytes("output.pdf", pdfBytes)
    End Sub
End Class

After (IronPDF)：

// NuGet: Install-Package IronPdf
using IronPdf;
using System.IO;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        var htmlContent = "<html><body><h1>Hello World</h1><p>This is a PDF document.</p></body></html>";
        var pdf = renderer.RenderHtmlAsPdf(htmlContent);
        pdf.SaveAs("output.pdf");
    }
}

// NuGet: Install-Package IronPdf
using IronPdf;
using System.IO;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        var htmlContent = "<html><body><h1>Hello World</h1><p>This is a PDF document.</p></body></html>";
        var pdf = renderer.RenderHtmlAsPdf(htmlContent);
        pdf.SaveAs("output.pdf");
    }
}

Imports IronPdf
Imports System.IO

Class Program
    Shared Sub Main()
        Dim renderer = New ChromePdfRenderer()
        Dim htmlContent = "<html><body><h1>Hello World</h1><p>This is a PDF document.</p></body></html>"
        Dim pdf = renderer.RenderHtmlAsPdf(htmlContent)
        pdf.SaveAs("output.pdf")
    End Sub
End Class

Imports IronPdf
Imports System.IO

Class Program
    Shared Sub Main()
        Dim renderer = New ChromePdfRenderer()
        Dim htmlContent = "<html><body><h1>Hello World</h1><p>This is a PDF document.</p></body></html>"
        Dim pdf = renderer.RenderHtmlAsPdf(htmlContent)
        pdf.SaveAs("output.pdf")
    End Sub
End Class

基本区别在于返回类型和保存模式。NReco PDF 生成器的File.WriteAllBytes()手动将其写入磁盘。IronPDF的PdfDocument对象。

这种面向对象的方法还有其他好处：您可以在保存之前对 PDF 进行操作（添加水印、合并文档、添加安全性）。如果您需要原始字节以与现有代码兼容，请使用pdf.BinaryData。有关其他渲染选项，请参阅 HTML to PDF 文档。

示例 2：带边距的自定义页面大小

之前（NReco PDF 生成器）：

// NuGet: Install-Package NReco.PdfGenerator
using NReco.PdfGenerator;
using System.IO;

class Program
{
    static void Main()
    {
        var htmlToPdf = new HtmlToPdfConverter();
        htmlToPdf.PageWidth = 210;
        htmlToPdf.PageHeight = 297;
        htmlToPdf.Margins = new PageMargins { Top = 10, Bottom = 10, Left = 10, Right = 10 };
        var htmlContent = "<html><body><h1>Custom Page Size</h1><p>A4 size document with margins.</p></body></html>";
        var pdfBytes = htmlToPdf.GeneratePdf(htmlContent);
        File.WriteAllBytes("custom-size.pdf", pdfBytes);
    }
}

// NuGet: Install-Package NReco.PdfGenerator
using NReco.PdfGenerator;
using System.IO;

class Program
{
    static void Main()
    {
        var htmlToPdf = new HtmlToPdfConverter();
        htmlToPdf.PageWidth = 210;
        htmlToPdf.PageHeight = 297;
        htmlToPdf.Margins = new PageMargins { Top = 10, Bottom = 10, Left = 10, Right = 10 };
        var htmlContent = "<html><body><h1>Custom Page Size</h1><p>A4 size document with margins.</p></body></html>";
        var pdfBytes = htmlToPdf.GeneratePdf(htmlContent);
        File.WriteAllBytes("custom-size.pdf", pdfBytes);
    }
}

Imports NReco.PdfGenerator
Imports System.IO

Class Program
    Shared Sub Main()
        Dim htmlToPdf = New HtmlToPdfConverter()
        htmlToPdf.PageWidth = 210
        htmlToPdf.PageHeight = 297
        htmlToPdf.Margins = New PageMargins With {.Top = 10, .Bottom = 10, .Left = 10, .Right = 10}
        Dim htmlContent = "<html><body><h1>Custom Page Size</h1><p>A4 size document with margins.</p></body></html>"
        Dim pdfBytes = htmlToPdf.GeneratePdf(htmlContent)
        File.WriteAllBytes("custom-size.pdf", pdfBytes)
    End Sub
End Class

Imports NReco.PdfGenerator
Imports System.IO

Class Program
    Shared Sub Main()
        Dim htmlToPdf = New HtmlToPdfConverter()
        htmlToPdf.PageWidth = 210
        htmlToPdf.PageHeight = 297
        htmlToPdf.Margins = New PageMargins With {.Top = 10, .Bottom = 10, .Left = 10, .Right = 10}
        Dim htmlContent = "<html><body><h1>Custom Page Size</h1><p>A4 size document with margins.</p></body></html>"
        Dim pdfBytes = htmlToPdf.GeneratePdf(htmlContent)
        File.WriteAllBytes("custom-size.pdf", pdfBytes)
    End Sub
End Class

After (IronPDF)：

// NuGet: Install-Package IronPdf
using IronPdf;
using IronPdf.Rendering;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        renderer.RenderingOptions.PaperSize = PdfPaperSize.A4;
        renderer.RenderingOptions.MarginTop = 10;
        renderer.RenderingOptions.MarginBottom = 10;
        renderer.RenderingOptions.MarginLeft = 10;
        renderer.RenderingOptions.MarginRight = 10;
        var htmlContent = "<html><body><h1>Custom Page Size</h1><p>A4 size document with margins.</p></body></html>";
        var pdf = renderer.RenderHtmlAsPdf(htmlContent);
        pdf.SaveAs("custom-size.pdf");
    }
}

// NuGet: Install-Package IronPdf
using IronPdf;
using IronPdf.Rendering;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        renderer.RenderingOptions.PaperSize = PdfPaperSize.A4;
        renderer.RenderingOptions.MarginTop = 10;
        renderer.RenderingOptions.MarginBottom = 10;
        renderer.RenderingOptions.MarginLeft = 10;
        renderer.RenderingOptions.MarginRight = 10;
        var htmlContent = "<html><body><h1>Custom Page Size</h1><p>A4 size document with margins.</p></body></html>";
        var pdf = renderer.RenderHtmlAsPdf(htmlContent);
        pdf.SaveAs("custom-size.pdf");
    }
}

Imports IronPdf
Imports IronPdf.Rendering

Class Program
    Shared Sub Main()
        Dim renderer = New ChromePdfRenderer()
        renderer.RenderingOptions.PaperSize = PdfPaperSize.A4
        renderer.RenderingOptions.MarginTop = 10
        renderer.RenderingOptions.MarginBottom = 10
        renderer.RenderingOptions.MarginLeft = 10
        renderer.RenderingOptions.MarginRight = 10
        Dim htmlContent = "<html><body><h1>Custom Page Size</h1><p>A4 size document with margins.</p></body></html>"
        Dim pdf = renderer.RenderHtmlAsPdf(htmlContent)
        pdf.SaveAs("custom-size.pdf")
    End Sub
End Class

Imports IronPdf
Imports IronPdf.Rendering

Class Program
    Shared Sub Main()
        Dim renderer = New ChromePdfRenderer()
        renderer.RenderingOptions.PaperSize = PdfPaperSize.A4
        renderer.RenderingOptions.MarginTop = 10
        renderer.RenderingOptions.MarginBottom = 10
        renderer.RenderingOptions.MarginLeft = 10
        renderer.RenderingOptions.MarginRight = 10
        Dim htmlContent = "<html><body><h1>Custom Page Size</h1><p>A4 size document with margins.</p></body></html>"
        Dim pdf = renderer.RenderHtmlAsPdf(htmlContent)
        pdf.SaveAs("custom-size.pdf")
    End Sub
End Class

NReco PDF Generator 使用数值维度 (PageWidth = 210, PageHeight = 297) 和一个PageMargins对象。IronPDF使用PdfPaperSize枚举（包括标准尺寸如 A4、Letter、Legal）和RenderingOptions对象上的单独边距属性。

关键的迁移变化：

PageHeight → RenderingOptions.PaperSize = PdfPaperSize.A4
new PageMargins { Top = 10, ... }→ Individual properties: RenderingOptions.MarginTop = 10

对于未在枚举中涵盖的自定义纸张尺寸，请使用RenderingOptions.SetCustomPaperSizeinMilimeters(width, height)。了解页面配置选项的更多信息。

示例 3：URL 到 PDF 的转换

之前（NReco PDF 生成器）：

// NuGet: Install-Package NReco.PdfGenerator
using NReco.PdfGenerator;
using System.IO;

class Program
{
    static void Main()
    {
        var htmlToPdf = new HtmlToPdfConverter();
        var pdfBytes = htmlToPdf.GeneratePdfFromFile("https://www.example.com", null);
        File.WriteAllBytes("webpage.pdf", pdfBytes);
    }
}

// NuGet: Install-Package NReco.PdfGenerator
using NReco.PdfGenerator;
using System.IO;

class Program
{
    static void Main()
    {
        var htmlToPdf = new HtmlToPdfConverter();
        var pdfBytes = htmlToPdf.GeneratePdfFromFile("https://www.example.com", null);
        File.WriteAllBytes("webpage.pdf", pdfBytes);
    }
}

Imports NReco.PdfGenerator
Imports System.IO

Class Program
    Shared Sub Main()
        Dim htmlToPdf As New HtmlToPdfConverter()
        Dim pdfBytes As Byte() = htmlToPdf.GeneratePdfFromFile("https://www.example.com", Nothing)
        File.WriteAllBytes("webpage.pdf", pdfBytes)
    End Sub
End Class

Imports NReco.PdfGenerator
Imports System.IO

Class Program
    Shared Sub Main()
        Dim htmlToPdf As New HtmlToPdfConverter()
        Dim pdfBytes As Byte() = htmlToPdf.GeneratePdfFromFile("https://www.example.com", Nothing)
        File.WriteAllBytes("webpage.pdf", pdfBytes)
    End Sub
End Class

After (IronPDF)：

// NuGet: Install-Package IronPdf
using IronPdf;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        var pdf = renderer.RenderUrlAsPdf("https://www.example.com");
        pdf.SaveAs("webpage.pdf");
    }
}

// NuGet: Install-Package IronPdf
using IronPdf;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        var pdf = renderer.RenderUrlAsPdf("https://www.example.com");
        pdf.SaveAs("webpage.pdf");
    }
}

Imports IronPdf

Class Program
    Shared Sub Main()
        Dim renderer As New ChromePdfRenderer()
        Dim pdf = renderer.RenderUrlAsPdf("https://www.example.com")
        pdf.SaveAs("webpage.pdf")
    End Sub
End Class

Imports IronPdf

Class Program
    Shared Sub Main()
        Dim renderer As New ChromePdfRenderer()
        Dim pdf = renderer.RenderUrlAsPdf("https://www.example.com")
        pdf.SaveAs("webpage.pdf")
    End Sub
End Class

NReco PDF Generator 使用令人困惑的GeneratePdfFromFile()方法来处理本地文件和 URL，第二个参数是可为空的。IronPDF提供专用方法: RenderUrlAsPdf()用于 URL，RenderHtmlFileAsPdf()用于本地 HTML 文件。

IronPDF 的方法更简洁且更直观。对于异步 Web 应用程序，请使用await renderer.RenderUrlAsPdfAsync(url)以避免阻塞线程——这是NReco PDF 生成器无法做到的。

关键迁移说明

缩放值转换

NReco PDF Generator 使用浮点数值（0.0-2.0），而IronPDF使用百分比整数：

// NReco PDF Generator: Zoom = 0.9f (90%)
// IronPDF: Zoom = 90

// Conversion formula:
int ironPdfZoom = (int)(nrecoZoom * 100);

// NReco PDF Generator: Zoom = 0.9f (90%)
// IronPDF: Zoom = 90

// Conversion formula:
int ironPdfZoom = (int)(nrecoZoom * 100);

' NReco PDF Generator: Zoom = 0.9F (90%)
' IronPDF: Zoom = 90

' Conversion formula:
Dim ironPdfZoom As Integer = CInt(nrecoZoom * 100)

' NReco PDF Generator: Zoom = 0.9F (90%)
' IronPDF: Zoom = 90

' Conversion formula:
Dim ironPdfZoom As Integer = CInt(nrecoZoom * 100)

占位符语法更新

必须更新所有页眉/页脚占位符：

NReco PDF 生成器	IronPDF
`[page]`	`{page}`
`[topage]`	`{total-pages}`
`[date]`	`{date}`
`[title]`	`{html-title}`

// NReco PDF Generator:
converter.PageFooterHtml = "<div>Page [page] of [topage]</div>";

// IronPDF:
renderer.RenderingOptions.HtmlFooter = new HtmlHeaderFooter
{
    HtmlFragment = "<div>Page {page} of {total-pages}</div>",
    MaxHeight = 20
};

// NReco PDF Generator:
converter.PageFooterHtml = "<div>Page [page] of [topage]</div>";

// IronPDF:
renderer.RenderingOptions.HtmlFooter = new HtmlHeaderFooter
{
    HtmlFragment = "<div>Page {page} of {total-pages}</div>",
    MaxHeight = 20
};

Imports NReco.PdfGenerator
Imports IronPdf

' NReco PDF Generator:
converter.PageFooterHtml = "<div>Page [page] of [topage]</div>"

' IronPDF:
renderer.RenderingOptions.HtmlFooter = New HtmlHeaderFooter With {
    .HtmlFragment = "<div>Page {page} of {total-pages}</div>",
    .MaxHeight = 20
}

Imports NReco.PdfGenerator
Imports IronPdf

' NReco PDF Generator:
converter.PageFooterHtml = "<div>Page [page] of [topage]</div>"

' IronPDF:
renderer.RenderingOptions.HtmlFooter = New HtmlHeaderFooter With {
    .HtmlFragment = "<div>Page {page} of {total-pages}</div>",
    .MaxHeight = 20
}

返回类型更改

NReco PDF Generator 直接返回byte[];IronPDF返回PdfDocument:

//NReco PDF 生成器pattern:
byte[] pdfBytes = converter.GeneratePdf(html);
File.WriteAllBytes("output.pdf", pdfBytes);

//IronPDFpattern:
var pdf = renderer.RenderHtmlAsPdf(html);
pdf.SaveAs("output.pdf");

// Or if you need bytes:
byte[] pdfBytes = renderer.RenderHtmlAsPdf(html).BinaryData;

//NReco PDF 生成器pattern:
byte[] pdfBytes = converter.GeneratePdf(html);
File.WriteAllBytes("output.pdf", pdfBytes);

//IronPDFpattern:
var pdf = renderer.RenderHtmlAsPdf(html);
pdf.SaveAs("output.pdf");

// Or if you need bytes:
byte[] pdfBytes = renderer.RenderHtmlAsPdf(html).BinaryData;

Imports System.IO

' NReco PDF 生成器pattern:
Dim pdfBytes As Byte() = converter.GeneratePdf(html)
File.WriteAllBytes("output.pdf", pdfBytes)

' IronPDFpattern:
Dim pdf = renderer.RenderHtmlAsPdf(html)
pdf.SaveAs("output.pdf")

' Or if you need bytes:
Dim pdfBytes As Byte() = renderer.RenderHtmlAsPdf(html).BinaryData

Imports System.IO

' NReco PDF 生成器pattern:
Dim pdfBytes As Byte() = converter.GeneratePdf(html)
File.WriteAllBytes("output.pdf", pdfBytes)

' IronPDFpattern:
Dim pdf = renderer.RenderHtmlAsPdf(html)
pdf.SaveAs("output.pdf")

' Or if you need bytes:
Dim pdfBytes As Byte() = renderer.RenderHtmlAsPdf(html).BinaryData

线程安全和可重用性

NReco PDF 生成器通常每次调用都会创建一个新的转换器。IronPDF的ChromePdfRenderer是线程安全的并且可以重用:

//NReco PDF 生成器pattern (creates new each time):
public byte[] Generate(string html)
{
    var converter = new HtmlToPdfConverter();
    return converter.GeneratePdf(html);
}

//IronPDFpattern (reuse renderer, thread-safe):
private readonly ChromePdfRenderer _renderer = new ChromePdfRenderer();

public byte[] Generate(string html)
{
    return _renderer.RenderHtmlAsPdf(html).BinaryData;
}

//NReco PDF 生成器pattern (creates new each time):
public byte[] Generate(string html)
{
    var converter = new HtmlToPdfConverter();
    return converter.GeneratePdf(html);
}

//IronPDFpattern (reuse renderer, thread-safe):
private readonly ChromePdfRenderer _renderer = new ChromePdfRenderer();

public byte[] Generate(string html)
{
    return _renderer.RenderHtmlAsPdf(html).BinaryData;
}

Imports NReco.PdfGenerator
Imports IronPdf

' NReco PDF 生成器pattern (creates new each time):
Public Function Generate(html As String) As Byte()
    Dim converter As New HtmlToPdfConverter()
    Return converter.GeneratePdf(html)
End Function

' IronPDFpattern (reuse renderer, thread-safe):
Private ReadOnly _renderer As New ChromePdfRenderer()

Public Function Generate(html As String) As Byte()
    Return _renderer.RenderHtmlAsPdf(html).BinaryData
End Function

Imports NReco.PdfGenerator
Imports IronPdf

' NReco PDF 生成器pattern (creates new each time):
Public Function Generate(html As String) As Byte()
    Dim converter As New HtmlToPdfConverter()
    Return converter.GeneratePdf(html)
End Function

' IronPDFpattern (reuse renderer, thread-safe):
Private ReadOnly _renderer As New ChromePdfRenderer()

Public Function Generate(html As String) As Byte()
    Return _renderer.RenderHtmlAsPdf(html).BinaryData
End Function

异步支持（新功能）

IronPDF 支持NReco PDF 生成器无法提供的Async/Await模式：

// NReco PDF Generator: No async support available

// IronPDF: Full async support
public async Task<byte[]> GenerateAsync(string html)
{
    var pdf = await _renderer.RenderHtmlAsPdfAsync(html);
    return pdf.BinaryData;
}

// NReco PDF Generator: No async support available

// IronPDF: Full async support
public async Task<byte[]> GenerateAsync(string html)
{
    var pdf = await _renderer.RenderHtmlAsPdfAsync(html);
    return pdf.BinaryData;
}

Imports System.Threading.Tasks

' NReco PDF Generator: No async support available

' IronPDF: Full async support
Public Async Function GenerateAsync(html As String) As Task(Of Byte())
    Dim pdf = Await _renderer.RenderHtmlAsPdfAsync(html)
    Return pdf.BinaryData
End Function

Imports System.Threading.Tasks

' NReco PDF Generator: No async support available

' IronPDF: Full async support
Public Async Function GenerateAsync(html As String) As Task(Of Byte())
    Dim pdf = Await _renderer.RenderHtmlAsPdfAsync(html)
    Return pdf.BinaryData
End Function

故障排除

问题 1：HtmlToPdfConverter 未找到

**问题:**IronPDF中不存在HtmlToPdfConverter类。

解决方案: 使用ChromePdfRenderer：

// NReco PDF Generator
var converter = new HtmlToPdfConverter();

// IronPDF
var renderer = new ChromePdfRenderer();

// NReco PDF Generator
var converter = new HtmlToPdfConverter();

// IronPDF
var renderer = new ChromePdfRenderer();

' NReco PDF Generator
Dim converter As New HtmlToPdfConverter()

' IronPDF
Dim renderer As New ChromePdfRenderer()

' NReco PDF Generator
Dim converter As New HtmlToPdfConverter()

' IronPDF
Dim renderer As New ChromePdfRenderer()

问题 2：GeneratePdf 返回错误类型

问题: 代码期望PdfDocument。

解决方案: 访问.BinaryData属性：

// NReco PDF Generator
byte[] pdfBytes = converter.GeneratePdf(html);

// IronPDF
byte[] pdfBytes = renderer.RenderHtmlAsPdf(html).BinaryData;

// NReco PDF Generator
byte[] pdfBytes = converter.GeneratePdf(html);

// IronPDF
byte[] pdfBytes = renderer.RenderHtmlAsPdf(html).BinaryData;

' NReco PDF Generator
Dim pdfBytes As Byte() = converter.GeneratePdf(html)

' IronPDF
Dim pdfBytes As Byte() = renderer.RenderHtmlAsPdf(html).BinaryData

' NReco PDF Generator
Dim pdfBytes As Byte() = converter.GeneratePdf(html)

' IronPDF
Dim pdfBytes As Byte() = renderer.RenderHtmlAsPdf(html).BinaryData

问题 3：未找到 PageMargins 对象

**问题:**IronPDF中不存在PageMargins类。

**解决方法：**使用单独的边距属性：

// NReco PDF Generator
converter.Margins = new PageMargins { Top = 10, Bottom = 10, Left = 10, Right = 10 };

// IronPDF
renderer.RenderingOptions.MarginTop = 10;
renderer.RenderingOptions.MarginBottom = 10;
renderer.RenderingOptions.MarginLeft = 10;
renderer.RenderingOptions.MarginRight = 10;

// NReco PDF Generator
converter.Margins = new PageMargins { Top = 10, Bottom = 10, Left = 10, Right = 10 };

// IronPDF
renderer.RenderingOptions.MarginTop = 10;
renderer.RenderingOptions.MarginBottom = 10;
renderer.RenderingOptions.MarginLeft = 10;
renderer.RenderingOptions.MarginRight = 10;

' NReco PDF Generator
converter.Margins = New PageMargins With {.Top = 10, .Bottom = 10, .Left = 10, .Right = 10}

' IronPDF
renderer.RenderingOptions.MarginTop = 10
renderer.RenderingOptions.MarginBottom = 10
renderer.RenderingOptions.MarginLeft = 10
renderer.RenderingOptions.MarginRight = 10

' NReco PDF Generator
converter.Margins = New PageMargins With {.Top = 10, .Bottom = 10, .Left = 10, .Right = 10}

' IronPDF
renderer.RenderingOptions.MarginTop = 10
renderer.RenderingOptions.MarginBottom = 10
renderer.RenderingOptions.MarginLeft = 10
renderer.RenderingOptions.MarginRight = 10

问题 4：页码未显示

问题: [topage]占位符不起作用。

**解决方案：**更新IronPDF占位符语法：

// NReco PDF Generator
converter.PageFooterHtml = "<div>Page [page] of [topage]</div>";

// IronPDF
renderer.RenderingOptions.HtmlFooter = new HtmlHeaderFooter
{
    HtmlFragment = "<div>Page {page} of {total-pages}</div>",
    MaxHeight = 20
};

// NReco PDF Generator
converter.PageFooterHtml = "<div>Page [page] of [topage]</div>";

// IronPDF
renderer.RenderingOptions.HtmlFooter = new HtmlHeaderFooter
{
    HtmlFragment = "<div>Page {page} of {total-pages}</div>",
    MaxHeight = 20
};

Imports NReco.PdfGenerator
Imports IronPdf

converter.PageFooterHtml = "<div>Page [page] of [topage]</div>"

renderer.RenderingOptions.HtmlFooter = New HtmlHeaderFooter With {
    .HtmlFragment = "<div>Page {page} of {total-pages}</div>",
    .MaxHeight = 20
}

Imports NReco.PdfGenerator
Imports IronPdf

converter.PageFooterHtml = "<div>Page [page] of [topage]</div>"

renderer.RenderingOptions.HtmlFooter = New HtmlHeaderFooter With {
    .HtmlFragment = "<div>Page {page} of {total-pages}</div>",
    .MaxHeight = 20
}