从 Foxit PDF SDK 迁移到 IronPdf：(.NET指南）

福昕 PDF 的挑战

Foxit PDF SDK 是一个功能强大的企业级库，但它也存在相当大的复杂性，可能会减慢开发速度：

1.复杂的许可系统：多种产品、SKU 和许可类型（按开发者、按服务器、OEM 等）使得为您的项目选择合适的选项变得困难。

2.企业定价：定价是为大型组织量身定制的，对于较小的团队或个人开发人员来说可能难以承受。

3.手动安装：福昕 PDF SDK需要手动 DLL 引用或私有 NuGet 源——没有简单的公共 NuGet 包可用。

4.冗长的 API：使用Library.Initialize()进行库初始化、错误代码检查以及显式调用Library.Release()会为每个操作增加大量的样板代码。

5.单独的 HTML 转换插件： HTML 到 PDF 的转换需要额外购买插件——它不包含在基本 SDK 中。

6.复杂配置：设置需要详细的对象配置（例如， HTML2PDFSettingData ），具有多个属性。

7. C++ 传承： API 模式反映了 C++ 的起源，在现代 C# 应用程序中感觉不太自然。

福昕 PDF 与IronPDF对比

成本效益分析

从 Foxit PDF 迁移到IronPDF可带来切实的开发优势：通过更简单的 API 降低复杂性，通过直观的方法加快开发速度，兼容现代 .NET，包括 async/await 和 LINQ 支持，采用 HTML 优先方法利用现有的 Web 技能，以及无需单独购买附加组件即可获得所有功能。 当您计划在 2025 年和 2026 年采用 .NET 10 和 C# 14 时，IronPDF 为 PDF 生成提供了一个面向未来的基础。

前提条件

1. .NET 环境：IronPDF支持 .NET Framework 4.6.2+、.NET Core 3.1+ 和 .NET 5/6/7/8/9+。
2. NuGet 访问权限：确保您可以从 NuGet 安装包。 3.许可证密钥：请从ironpdf.com获取用于生产环境的IronPDF许可证密钥。

备份您的项目

# Create a backup branch
git checkout -b pre-ironpdf-migration
git add .
git commit -m "Backup before福昕 PDF SDKtoIronPDFmigration"

# Create a backup branch
git checkout -b pre-ironpdf-migration
git add .
git commit -m "Backup before福昕 PDF SDKtoIronPDFmigration"

识别所有福昕 PDF 使用情况

# Find all福昕 PDF SDKreferences
grep -r "foxit\|PDFDoc\|PDFPage\|Library.Initialize\|Library.Release" --include="*.cs" --include="*.csproj" .

# Find Foxit DLL references
find . -name "*.csproj" | xargs grep -l "Foxit\|fsdk"

# Find all福昕 PDF SDKreferences
grep -r "foxit\|PDFDoc\|PDFPage\|Library.Initialize\|Library.Release" --include="*.cs" --include="*.csproj" .

# Find Foxit DLL references
find . -name "*.csproj" | xargs grep -l "Foxit\|fsdk"

文档当前功能

在迁移之前，编目：

• 您使用的福昕 PDF 功能（HTML 转换、注释、表单、安全性）
• 许可证密钥位置和初始化代码
• 自定义配置和设置
• 使用 ErrorCode 枚举的错误处理模式

步骤 1：更新 NuGet 软件包

#福昕 PDF SDKtypically requires manual removal of DLL references
# Check your .csproj for Foxit references and remove them

# Install IronPDF
dotnet add package IronPdf

#福昕 PDF SDKtypically requires manual removal of DLL references
# Check your .csproj for Foxit references and remove them

# Install IronPDF
dotnet add package IronPdf

如果您在 .csproj 中有福昕 PDF 引用，请手动将其删除：

<!-- Remove these manually -->
<Reference Include="fsdk_dotnet">
    <HintPath>..\libs\Foxit\fsdk_dotnet.dll</HintPath>
</Reference>

<!-- Remove these manually -->
<Reference Include="fsdk_dotnet">
    <HintPath>..\libs\Foxit\fsdk_dotnet.dll</HintPath>
</Reference>

步骤 2：更新命名空间

// Before (Foxit PDF)
using foxit;
using foxit.common;
using foxit.common.fxcrt;
using foxit.pdf;
using foxit.pdf.annots;
using foxit.addon.conversion;

// After (IronPDF)
using IronPdf;
using IronPdf.Rendering;
using IronPdf.Editing;

// Before (Foxit PDF)
using foxit;
using foxit.common;
using foxit.common.fxcrt;
using foxit.pdf;
using foxit.pdf.annots;
using foxit.addon.conversion;

// After (IronPDF)
using IronPdf;
using IronPdf.Rendering;
using IronPdf.Editing;

第 3 步：初始化 IronPDF.

此次福昕 PDF 迁移中最重要的改进之一是消除了复杂的初始化和清理模式：

// Before (Foxit PDF)
string sn = "YOUR_SERIAL_NUMBER";
string key = "YOUR_LICENSE_KEY";
ErrorCode error_code = Library.Initialize(sn, key);
if (error_code != ErrorCode.e_ErrSuccess)
{
    throw new Exception("Failed to initialize Foxit PDF SDK");
}
// ... your code ...
Library.Release();  // Don't forget this!

// After (IronPDF)
IronPdf.License.LicenseKey = "YOUR-IRONPDF-LICENSE-KEY";
// That's it! No Release() needed

// Before (Foxit PDF)
string sn = "YOUR_SERIAL_NUMBER";
string key = "YOUR_LICENSE_KEY";
ErrorCode error_code = Library.Initialize(sn, key);
if (error_code != ErrorCode.e_ErrSuccess)
{
    throw new Exception("Failed to initialize Foxit PDF SDK");
}
// ... your code ...
Library.Release();  // Don't forget this!

// After (IronPDF)
IronPdf.License.LicenseKey = "YOUR-IRONPDF-LICENSE-KEY";
// That's it! No Release() needed

步骤 4：基本转换模式

// Before (Foxit PDF)
Library.Initialize(sn, key);
HTML2PDFSettingData settings = new HTML2PDFSettingData();
settings.page_width = 612.0f;
settings.page_height = 792.0f;
using (HTML2PDF html2pdf = new HTML2PDF(settings))
{
    html2pdf.Convert(htmlContent, "output.pdf");
}
Library.Release();

// After (IronPDF)
var renderer = new ChromePdfRenderer();
var pdf = renderer.RenderHtmlAsPdf(htmlContent);
pdf.SaveAs("output.pdf");

// Before (Foxit PDF)
Library.Initialize(sn, key);
HTML2PDFSettingData settings = new HTML2PDFSettingData();
settings.page_width = 612.0f;
settings.page_height = 792.0f;
using (HTML2PDF html2pdf = new HTML2PDF(settings))
{
    html2pdf.Convert(htmlContent, "output.pdf");
}
Library.Release();

// After (IronPDF)
var renderer = new ChromePdfRenderer();
var pdf = renderer.RenderHtmlAsPdf(htmlContent);
pdf.SaveAs("output.pdf");

命名空间映射

核心类映射

PDFDoc 方法

HTML2PDF/转换

水印设置

示例 1：HTML 到 PDF 的转换

之前（福昕 PDF SDK）：

// NuGet: Install-Package Foxit.SDK
using Foxit.SDK;
using Foxit.SDK.Common;
using Foxit.SDK.PDFConversion;
using System;

class Program
{
    static void Main()
    {
        Library.Initialize("sn", "key");

        HTML2PDFSettingData settingData = new HTML2PDFSettingData();
        settingData.page_width = 612.0f;
        settingData.page_height = 792.0f;
        settingData.page_mode = HTML2PDFPageMode.e_HTML2PDFPageModeSinglePage;

        using (HTML2PDF html2pdf = new HTML2PDF(settingData))
        {
            html2pdf.Convert("<html><body><h1>Hello World</h1></body></html>", "output.pdf");
        }

        Library.Release();
    }
}

// NuGet: Install-Package Foxit.SDK
using Foxit.SDK;
using Foxit.SDK.Common;
using Foxit.SDK.PDFConversion;
using System;

class Program
{
    static void Main()
    {
        Library.Initialize("sn", "key");

        HTML2PDFSettingData settingData = new HTML2PDFSettingData();
        settingData.page_width = 612.0f;
        settingData.page_height = 792.0f;
        settingData.page_mode = HTML2PDFPageMode.e_HTML2PDFPageModeSinglePage;

        using (HTML2PDF html2pdf = new HTML2PDF(settingData))
        {
            html2pdf.Convert("<html><body><h1>Hello World</h1></body></html>", "output.pdf");
        }

        Library.Release();
    }
}

After (IronPDF)：

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

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

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

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

IronPDF 方法将 15 行以上的配置代码减少到仅 4 行。 没有库初始化，没有显式清理，没有复杂的设置对象。 有关更多 HTML 渲染选项，请参阅 HTML to PDF 文档。

示例 2：URL 到 PDF 的转换

之前（福昕 PDF SDK）：

// NuGet: Install-Package Foxit.SDK
using Foxit.SDK;
using Foxit.SDK.Common;
using Foxit.SDK.PDFConversion;
using System;

class Program
{
    static void Main()
    {
        Library.Initialize("sn", "key");

        HTML2PDFSettingData settingData = new HTML2PDFSettingData();
        settingData.page_width = 612.0f;
        settingData.page_height = 792.0f;
        settingData.page_mode = HTML2PDFPageMode.e_HTML2PDFPageModeSinglePage;

        using (HTML2PDF html2pdf = new HTML2PDF(settingData))
        {
            html2pdf.ConvertFromURL("https://www.example.com", "output.pdf");
        }

        Library.Release();
    }
}

// NuGet: Install-Package Foxit.SDK
using Foxit.SDK;
using Foxit.SDK.Common;
using Foxit.SDK.PDFConversion;
using System;

class Program
{
    static void Main()
    {
        Library.Initialize("sn", "key");

        HTML2PDFSettingData settingData = new HTML2PDFSettingData();
        settingData.page_width = 612.0f;
        settingData.page_height = 792.0f;
        settingData.page_mode = HTML2PDFPageMode.e_HTML2PDFPageModeSinglePage;

        using (HTML2PDF html2pdf = new HTML2PDF(settingData))
        {
            html2pdf.ConvertFromURL("https://www.example.com", "output.pdf");
        }

        Library.Release();
    }
}

After (IronPDF)：

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

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

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

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

IronPDF 内置的 Chromium 引擎可自动处理 JavaScript 执行、CSS 渲染和动态内容。 了解有关 URL 至 PDF 转换的更多信息。

示例 3：添加水印

之前（福昕 PDF SDK）：

// NuGet: Install-Package Foxit.SDK
using Foxit.SDK;
using Foxit.SDK.Common;
using Foxit.SDK.PDFDoc;
using System;

class Program
{
    static void Main()
    {
        Library.Initialize("sn", "key");

        using (PDFDoc doc = new PDFDoc("input.pdf"))
        {
            doc.Load("");

            Watermark watermark = new Watermark(doc, "Confidential", 
                new Font(Font.StandardID.e_StdIDHelvetica), 48.0f, 0xFF0000FF);

            WatermarkSettings settings = new WatermarkSettings();
            settings.flags = Watermark.e_WatermarkFlagASPageContents;
            settings.position = Watermark.Position.e_PosCenter;
            settings.rotation = -45.0f;
            settings.opacity = 0.5f;

            watermark.SetSettings(settings);
            watermark.InsertToAllPages();

            doc.SaveAs("output.pdf", PDFDoc.SaveFlags.e_SaveFlagNoOriginal);
        }

        Library.Release();
    }
}

// NuGet: Install-Package Foxit.SDK
using Foxit.SDK;
using Foxit.SDK.Common;
using Foxit.SDK.PDFDoc;
using System;

class Program
{
    static void Main()
    {
        Library.Initialize("sn", "key");

        using (PDFDoc doc = new PDFDoc("input.pdf"))
        {
            doc.Load("");

            Watermark watermark = new Watermark(doc, "Confidential", 
                new Font(Font.StandardID.e_StdIDHelvetica), 48.0f, 0xFF0000FF);

            WatermarkSettings settings = new WatermarkSettings();
            settings.flags = Watermark.e_WatermarkFlagASPageContents;
            settings.position = Watermark.Position.e_PosCenter;
            settings.rotation = -45.0f;
            settings.opacity = 0.5f;

            watermark.SetSettings(settings);
            watermark.InsertToAllPages();

            doc.SaveAs("output.pdf", PDFDoc.SaveFlags.e_SaveFlagNoOriginal);
        }

        Library.Release();
    }
}

After (IronPDF)：

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

class Program
{
    static void Main()
    {
        var pdf = PdfDocument.FromFile("input.pdf");
        pdf.ApplyWatermark(new TextStamper()
        {
            Text = "Confidential",
            FontSize = 48,
            Opacity = 50,
            Rotation = -45,
            VerticalAlignment = VerticalAlignment.Middle,
            HorizontalAlignment = HorizontalAlignment.Center
        });
        pdf.SaveAs("output.pdf");
    }
}

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

class Program
{
    static void Main()
    {
        var pdf = PdfDocument.FromFile("input.pdf");
        pdf.ApplyWatermark(new TextStamper()
        {
            Text = "Confidential",
            FontSize = 48,
            Opacity = 50,
            Rotation = -45,
            VerticalAlignment = VerticalAlignment.Middle,
            HorizontalAlignment = HorizontalAlignment.Center
        });
        pdf.SaveAs("output.pdf");
    }
}

IronPDF 的 TextStamper 提供基于属性的直观配置，而不是单独的设置对象和手动页面迭代。 有关其他选项，请参阅完整的 watermarking 文档。

示例 4：URL 转 PDF，带页眉和页脚

之前（福昕 PDF SDK）：

using foxit;
using foxit.addon.conversion;

class Program
{
    static void Main()
    {
        Library.Initialize("sn", "key");

        try
        {
            HTML2PDFSettingData settings = new HTML2PDFSettingData();
            settings.page_width = 595.0f;  // A4
            settings.page_height = 842.0f;
            settings.page_margin_top = 100.0f;
            settings.page_margin_bottom = 100.0f;

            //福昕 PDF SDKhas limited header/footer support
            // Often requires post-processing or additional code

            using (HTML2PDF html2pdf = new HTML2PDF(settings))
            {
                html2pdf.ConvertFromURL("https://www.example.com", "webpage.pdf");
            }
        }
        finally
        {
            Library.Release();
        }
    }
}

using foxit;
using foxit.addon.conversion;

class Program
{
    static void Main()
    {
        Library.Initialize("sn", "key");

        try
        {
            HTML2PDFSettingData settings = new HTML2PDFSettingData();
            settings.page_width = 595.0f;  // A4
            settings.page_height = 842.0f;
            settings.page_margin_top = 100.0f;
            settings.page_margin_bottom = 100.0f;

            //福昕 PDF SDKhas limited header/footer support
            // Often requires post-processing or additional code

            using (HTML2PDF html2pdf = new HTML2PDF(settings))
            {
                html2pdf.ConvertFromURL("https://www.example.com", "webpage.pdf");
            }
        }
        finally
        {
            Library.Release();
        }
    }
}

After (IronPDF)：

using IronPdf;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        renderer.RenderingOptions.PaperSize = PdfPaperSize.A4;
        renderer.RenderingOptions.PrintHtmlBackgrounds = true;
        renderer.RenderingOptions.WaitFor.RenderDelay(3000);  // Wait for JS

        // Built-in header/footer support
        renderer.RenderingOptions.HtmlHeader = new HtmlHeaderFooter()
        {
            HtmlFragment = "<div style='text-align:center; font-size:12pt;'>Company Report</div>",
            DrawDividerLine = true
        };

        renderer.RenderingOptions.HtmlFooter = new HtmlHeaderFooter()
        {
            HtmlFragment = "<div style='text-align:right; font-size:10pt;'>Page {page} of {total-pages}</div>",
            DrawDividerLine = true
        };

        var pdf = renderer.RenderUrlAsPdf("https://www.example.com");
        pdf.SaveAs("webpage.pdf");
    }
}

using IronPdf;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        renderer.RenderingOptions.PaperSize = PdfPaperSize.A4;
        renderer.RenderingOptions.PrintHtmlBackgrounds = true;
        renderer.RenderingOptions.WaitFor.RenderDelay(3000);  // Wait for JS

        // Built-in header/footer support
        renderer.RenderingOptions.HtmlHeader = new HtmlHeaderFooter()
        {
            HtmlFragment = "<div style='text-align:center; font-size:12pt;'>Company Report</div>",
            DrawDividerLine = true
        };

        renderer.RenderingOptions.HtmlFooter = new HtmlHeaderFooter()
        {
            HtmlFragment = "<div style='text-align:right; font-size:10pt;'>Page {page} of {total-pages}</div>",
            DrawDividerLine = true
        };

        var pdf = renderer.RenderUrlAsPdf("https://www.example.com");
        pdf.SaveAs("webpage.pdf");
    }
}

IronPdf 提供本地页眉和页脚支持，具有 HTML 风格和动态页码占位符。

示例 5：PDF 安全性和加密

之前（福昕 PDF SDK）：

using foxit;
using foxit.pdf;

class Program
{
    static void Main()
    {
        Library.Initialize("sn", "key");

        try
        {
            using (PDFDoc doc = new PDFDoc("input.pdf"))
            {
                doc.LoadW("");

                StdSecurityHandler securityHandler = new StdSecurityHandler();
                securityHandler.Initialize(
                    StdSecurityHandler.EncryptAlgorithm.e_CipherAES,
                    "user_password",
                    "owner_password",
                    PDFDoc.Permission.e_PermPrint | PDFDoc.Permission.e_PermModify,
                    128);

                doc.SetSecurityHandler(securityHandler);
                doc.SaveAs("encrypted.pdf", (int)PDFDoc.SaveFlags.e_SaveFlagNoOriginal);
            }
        }
        finally
        {
            Library.Release();
        }
    }
}

using foxit;
using foxit.pdf;

class Program
{
    static void Main()
    {
        Library.Initialize("sn", "key");

        try
        {
            using (PDFDoc doc = new PDFDoc("input.pdf"))
            {
                doc.LoadW("");

                StdSecurityHandler securityHandler = new StdSecurityHandler();
                securityHandler.Initialize(
                    StdSecurityHandler.EncryptAlgorithm.e_CipherAES,
                    "user_password",
                    "owner_password",
                    PDFDoc.Permission.e_PermPrint | PDFDoc.Permission.e_PermModify,
                    128);

                doc.SetSecurityHandler(securityHandler);
                doc.SaveAs("encrypted.pdf", (int)PDFDoc.SaveFlags.e_SaveFlagNoOriginal);
            }
        }
        finally
        {
            Library.Release();
        }
    }
}

After (IronPDF)：

using IronPdf;

class Program
{
    static void Main()
    {
        var pdf = PdfDocument.FromFile("input.pdf");

        // Set passwords
        pdf.SecuritySettings.OwnerPassword = "owner_password";
        pdf.SecuritySettings.UserPassword = "user_password";

        // Set permissions
        pdf.SecuritySettings.AllowUserPrinting = IronPdf.Security.PdfPrintSecurity.FullPrintRights;
        pdf.SecuritySettings.AllowUserEdits = IronPdf.Security.PdfEditSecurity.EditAll;
        pdf.SecuritySettings.AllowUserCopyPasteContent = true;
        pdf.SecuritySettings.AllowUserAnnotations = true;

        pdf.SaveAs("encrypted.pdf");
    }
}

using IronPdf;

class Program
{
    static void Main()
    {
        var pdf = PdfDocument.FromFile("input.pdf");

        // Set passwords
        pdf.SecuritySettings.OwnerPassword = "owner_password";
        pdf.SecuritySettings.UserPassword = "user_password";

        // Set permissions
        pdf.SecuritySettings.AllowUserPrinting = IronPdf.Security.PdfPrintSecurity.FullPrintRights;
        pdf.SecuritySettings.AllowUserEdits = IronPdf.Security.PdfEditSecurity.EditAll;
        pdf.SecuritySettings.AllowUserCopyPasteContent = true;
        pdf.SecuritySettings.AllowUserAnnotations = true;

        pdf.SaveAs("encrypted.pdf");
    }
}

重用 ChromePdfRenderer。

为了在福昕 PDF 迁移过程中获得最佳性能，请重复使用<代码>ChromePdfRenderer</代码实例--它是线程安全的：

// GOOD - Reuse renderer (thread-safe)
public class PdfService
{
    private static readonly ChromePdfRenderer _renderer = new ChromePdfRenderer();

    public byte[] Generate(string html) => _renderer.RenderHtmlAsPdf(html).BinaryData;
}

// BAD - Creates new instance each time
public byte[] GenerateBad(string html)
{
    var renderer = new ChromePdfRenderer();  // Wasteful
    return renderer.RenderHtmlAsPdf(html).BinaryData;
}

// GOOD - Reuse renderer (thread-safe)
public class PdfService
{
    private static readonly ChromePdfRenderer _renderer = new ChromePdfRenderer();

    public byte[] Generate(string html) => _renderer.RenderHtmlAsPdf(html).BinaryData;
}

// BAD - Creates new instance each time
public byte[] GenerateBad(string html)
{
    var renderer = new ChromePdfRenderer();  // Wasteful
    return renderer.RenderHtmlAsPdf(html).BinaryData;
}

单元转换助手

Foxit PDF SDK 使用点； IronPdf 使用毫米。 在迁移过程中使用此辅助工具：

public static class UnitConverter
{
    public static double PointsToMm(double points) => points * 0.352778;
    public static double MmToPoints(double mm) => mm / 0.352778;
    public static double InchesToMm(double inches) => inches * 25.4;
}

// Usage: Convert Foxit's 72 points (1 inch) toIronPDFmillimeters
renderer.RenderingOptions.MarginTop = UnitConverter.PointsToMm(72); // ~25.4mm

public static class UnitConverter
{
    public static double PointsToMm(double points) => points * 0.352778;
    public static double MmToPoints(double mm) => mm / 0.352778;
    public static double InchesToMm(double inches) => inches * 25.4;
}

// Usage: Convert Foxit's 72 points (1 inch) toIronPDFmillimeters
renderer.RenderingOptions.MarginTop = UnitConverter.PointsToMm(72); // ~25.4mm

正确的资源处置

// GOOD - Using statement for automatic cleanup
using (var pdf = PdfDocument.FromFile("large.pdf"))
{
    string text = pdf.ExtractAllText();
}  // pdf is disposed automatically

// GOOD - Using statement for automatic cleanup
using (var pdf = PdfDocument.FromFile("large.pdf"))
{
    string text = pdf.ExtractAllText();
}  // pdf is disposed automatically

问题 1：Library.Initialize() 未找到

问题：IronPDF中不存在Library.Initialize() 。

解决方案：IronPDF使用了一种更简单的初始化模式：

// Foxit PDF
Library.Initialize(sn, key);

//IronPDF- just set license key once at startup
IronPdf.License.LicenseKey = "YOUR-KEY";

// Foxit PDF
Library.Initialize(sn, key);

//IronPDF- just set license key once at startup
IronPdf.License.LicenseKey = "YOUR-KEY";

问题 2：错误代码处理

问题：代码检查ErrorCode.e_ErrSuccess ，但IronPDF没有这个属性。

解决方案：使用标准的.NET异常处理：

// Foxit PDF
ErrorCode err = doc.LoadW("");
if (err != ErrorCode.e_ErrSuccess) { /* handle error */ }

// IronPDF
try
{
    var pdf = PdfDocument.FromFile("input.pdf");
}
catch (IOException ex)
{
    Console.WriteLine($"Failed to load PDF: {ex.Message}");
}

// Foxit PDF
ErrorCode err = doc.LoadW("");
if (err != ErrorCode.e_ErrSuccess) { /* handle error */ }

// IronPDF
try
{
    var pdf = PdfDocument.FromFile("input.pdf");
}
catch (IOException ex)
{
    Console.WriteLine($"Failed to load PDF: {ex.Message}");
}

问题 3：PDFDoc.Close() 未找到

问题：IronPDF中不存在doc.Close()方法。

解决方法：使用Dispose()或using语句：

// Foxit PDF
doc.Close();

// IronPDF
pdf.Dispose();
// or better: wrap in using statement

// Foxit PDF
doc.Close();

// IronPDF
pdf.Dispose();
// or better: wrap in using statement

迁移前

• 清点所有已使用的福昕 PDF SDK功能
• 文档许可证密钥位置
• 注意所有Library.Initialize()和Library.Release()调用
• 列出自定义设置（页面大小、边距等）
• 使用 ErrorCode 识别错误处理模式
• 将项目备份到版本控制系统
• 获取IronPDF许可证密钥

软件包迁移

• 从 .csproj 文件中移除福昕 PDF SDKDLL 引用
• 删除所有私有 NuGet 源配置 安装 IronPdf NuGet 包： dotnet add package IronPdf
• 更新命名空间导入
• 在启动时设置IronPDF许可证密钥

代码迁移

• 移除Library.Initialize()和Library.Release()调用
• 将ErrorCode检查替换为 try/catch 语句。
• 将PDFDoc替换为PdfDocument
• 将HTML2PDF替换为ChromePdfRenderer
• 将页面访问权限从GetPage(i)更新为Pages[i]
• 将SaveAs(path, flags)替换为SaveAs(path)
• 将Close()替换为Dispose()或 using 语句
• 更新水印代码，使用TextStamper
• 将单位从点转换为毫米

测试

• 验证 HTML 转 PDF 输出是否符合预期
• 测试 PDF 加载和文本提取
• 验证合并功能
• 检查水印外观
• 测试安全/加密功能
• 验证表单字段操作
• 性能测试

后迁移

• 删除福昕 PDF SDKDLL 文件
• 删除与 Foxit 相关的配置文件
• 更新文档
• 清理未使用的辅助代码

迁移。