How to Migrate from fo.net to IronPDF

# Create a backup branch
git checkout -b pre-ironpdf-migration
git add .
git commit -m "Backup before fo.net to IronPDF migration"

# Find all fo.net references
grep -r "FonetDriver\|Fonet\|\.fo\"\|xsl-region" --include="*.cs" --include="*.csproj" .

# Find all XSL-FO template files
find . -name "*.fo" -o -name "*.xslfo" -o -name "*xsl-fo*"

# Remove fo.net package
dotnet remove package Fonet
dotnet remove package FO.NET

# Install IronPDF
dotnet add package IronPdf

// Before (fo.net)
using Fonet;
using Fonet.Render.Pdf;
using System.Xml;

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

Imports IronPdf
Imports IronPdf.Rendering

// Set license key at application startup
IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY";

' Set license key at application startup
IronPdf.License.LicenseKey = "YOUR-LICENSE-KEY"

// Before (fo.net with XSL-FO)
FonetDriver driver = FonetDriver.Make();
using (FileStream output = new FileStream("output.pdf", FileMode.Create))
{
    driver.Render(new StringReader(xslFoContent), output);
}

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

Imports System.IO
Imports Fonet
Imports IronPdf

' Before (fo.net with XSL-FO)
Dim driver As FonetDriver = FonetDriver.Make()
Using output As FileStream = New FileStream("output.pdf", FileMode.Create)
    driver.Render(New StringReader(xslFoContent), output)
End Using

' After (IronPDF with HTML)
Dim renderer As New ChromePdfRenderer()
Dim pdf = renderer.RenderHtmlAsPdf(htmlContent)
pdf.SaveAs("output.pdf")

// NuGet: Install-Package Fonet
using Fonet;
using Fonet.Render.Pdf;
using System.IO;
using System.Xml;

class Program
{
    static void Main()
    {
        // fo.net requires XSL-FO format, not HTML
        // First convert HTML to XSL-FO (manual process)
        string xslFo = @"<?xml version='1.0' encoding='utf-8'?>
            <fo:root xmlns:fo='http://www.w3.org/1999/XSL/Format'>
                <fo:layout-master-set>
                    <fo:simple-page-master master-name='page'>
                        <fo:region-body/>
                    </fo:simple-page-master>
                </fo:layout-master-set>
                <fo:page-sequence master-reference='page'>
                    <fo:flow flow-name='xsl-region-body'>
                        <fo:block>Hello World</fo:block>
                    </fo:flow>
                </fo:page-sequence>
            </fo:root>";

        FonetDriver driver = FonetDriver.Make();
        driver.Render(new StringReader(xslFo), 
            new FileStream("output.pdf", FileMode.Create));
    }
}

Imports Fonet
Imports Fonet.Render.Pdf
Imports System.IO
Imports System.Xml

Module Program
    Sub Main()
        ' fo.net requires XSL-FO format, not HTML
        ' First convert HTML to XSL-FO (manual process)
        Dim xslFo As String = "<?xml version='1.0' encoding='utf-8'?>" & _
            "<fo:root xmlns:fo='http://www.w3.org/1999/XSL/Format'>" & _
                "<fo:layout-master-set>" & _
                    "<fo:simple-page-master master-name='page'>" & _
                        "<fo:region-body/>" & _
                    "</fo:simple-page-master>" & _
                "</fo:layout-master-set>" & _
                "<fo:page-sequence master-reference='page'>" & _
                    "<fo:flow flow-name='xsl-region-body'>" & _
                        "<fo:block>Hello World</fo:block>" & _
                    "</fo:flow>" & _
                "</fo:page-sequence>" & _
            "</fo:root>"

        Dim driver As FonetDriver = FonetDriver.Make()
        driver.Render(New StringReader(xslFo), 
            New FileStream("output.pdf", FileMode.Create))
    End Sub
End Module

// NuGet: Install-Package IronPdf
using IronPdf;

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

Imports IronPdf

Class Program
    Shared Sub Main()
        Dim renderer = New ChromePdfRenderer()
        Dim html As String = "<h1>Hello World</h1><p>This is HTML content.</p>"
        Dim pdf = renderer.RenderHtmlAsPdf(html)
        pdf.SaveAs("output.pdf")
    End Sub
End Class

// NuGet: Install-Package Fonet
using Fonet;
using Fonet.Render.Pdf;
using System.IO;

class Program
{
    static void Main()
    {
        // fo.net settings are configured in XSL-FO markup
        string xslFo = @"<?xml version='1.0' encoding='utf-8'?>
            <fo:root xmlns:fo='http://www.w3.org/1999/XSL/Format'>
                <fo:layout-master-set>
                    <fo:simple-page-master master-name='A4' 
                        page-height='297mm' page-width='210mm'
                        margin-top='20mm' margin-bottom='20mm'
                        margin-left='25mm' margin-right='25mm'>
                        <fo:region-body/>
                    </fo:simple-page-master>
                </fo:layout-master-set>
                <fo:page-sequence master-reference='A4'>
                    <fo:flow flow-name='xsl-region-body'>
                        <fo:block font-size='14pt'>Custom PDF</fo:block>
                    </fo:flow>
                </fo:page-sequence>
            </fo:root>";

        FonetDriver driver = FonetDriver.Make();
        driver.Render(new StringReader(xslFo), 
            new FileStream("custom.pdf", FileMode.Create));
    }
}

Imports Fonet
Imports Fonet.Render.Pdf
Imports System.IO

Class Program
    Shared Sub Main()
        ' fo.net settings are configured in XSL-FO markup
        Dim xslFo As String = "<?xml version='1.0' encoding='utf-8'?>" & _
            "<fo:root xmlns:fo='http://www.w3.org/1999/XSL/Format'>" & _
                "<fo:layout-master-set>" & _
                    "<fo:simple-page-master master-name='A4' " & _
                        "page-height='297mm' page-width='210mm' " & _
                        "margin-top='20mm' margin-bottom='20mm' " & _
                        "margin-left='25mm' margin-right='25mm'>" & _
                        "<fo:region-body/>" & _
                    "</fo:simple-page-master>" & _
                "</fo:layout-master-set>" & _
                "<fo:page-sequence master-reference='A4'>" & _
                    "<fo:flow flow-name='xsl-region-body'>" & _
                        "<fo:block font-size='14pt'>Custom PDF</fo:block>" & _
                    "</fo:flow>" & _
                "</fo:page-sequence>" & _
            "</fo:root>"

        Dim driver As FonetDriver = FonetDriver.Make()
        driver.Render(New StringReader(xslFo), 
            New FileStream("custom.pdf", FileMode.Create))
    End Sub
End Class

// NuGet: Install-Package IronPdf
using IronPdf;
using IronPdf.Engines.Chrome;

class Program
{
    static void Main()
    {
        var renderer = new ChromePdfRenderer();
        renderer.RenderingOptions.PaperSize = PdfPaperSize.A4;
        renderer.RenderingOptions.MarginTop = 20;
        renderer.RenderingOptions.MarginBottom = 20;
        renderer.RenderingOptions.MarginLeft = 25;
        renderer.RenderingOptions.MarginRight = 25;

        string html = "<h1 style='font-size:14pt'>Custom PDF</h1>";
        var pdf = renderer.RenderHtmlAsPdf(html);
        pdf.SaveAs("custom.pdf");
    }
}

Imports IronPdf
Imports IronPdf.Engines.Chrome

Class Program
    Shared Sub Main()
        Dim renderer As New ChromePdfRenderer()
        renderer.RenderingOptions.PaperSize = PdfPaperSize.A4
        renderer.RenderingOptions.MarginTop = 20
        renderer.RenderingOptions.MarginBottom = 20
        renderer.RenderingOptions.MarginLeft = 25
        renderer.RenderingOptions.MarginRight = 25

        Dim html As String = "<h1 style='font-size:14pt'>Custom PDF</h1>"
        Dim pdf = renderer.RenderHtmlAsPdf(html)
        pdf.SaveAs("custom.pdf")
    End Sub
End Class

// NuGet: Install-Package Fonet
using Fonet;
using System.IO;
using System.Net;

class Program
{
    static void Main()
    {
        // fo.net does not support URL rendering directly
        // Must manually download, convert HTML to XSL-FO, then render
        string url = "https://example.com";
        string html = new WebClient().DownloadString(url);

        // Manual conversion from HTML to XSL-FO required (complex)
        string xslFo = ConvertHtmlToXslFo(html); // Not built-in

        FonetDriver driver = FonetDriver.Make();
        driver.Render(new StringReader(xslFo), 
            new FileStream("webpage.pdf", FileMode.Create));
    }

    static string ConvertHtmlToXslFo(string html)
    {
        // Custom implementation required - extremely complex
        throw new System.NotImplementedException();
    }
}

Imports Fonet
Imports System.IO
Imports System.Net

Class Program
    Shared Sub Main()
        ' fo.net does not support URL rendering directly
        ' Must manually download, convert HTML to XSL-FO, then render
        Dim url As String = "https://example.com"
        Dim html As String = New WebClient().DownloadString(url)

        ' Manual conversion from HTML to XSL-FO required (complex)
        Dim xslFo As String = ConvertHtmlToXslFo(html) ' Not built-in

        Dim driver As FonetDriver = FonetDriver.Make()
        driver.Render(New StringReader(xslFo), 
                      New FileStream("webpage.pdf", FileMode.Create))
    End Sub

    Shared Function ConvertHtmlToXslFo(html As String) As String
        ' Custom implementation required - extremely complex
        Throw New System.NotImplementedException()
    End Function
End Class

// NuGet: Install-Package IronPdf
using IronPdf;

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

Imports IronPdf

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

<fo:static-content flow-name="xsl-region-before">
    <fo:block text-align="center" font-size="10pt">
        Company Name - Confidential
    </fo:block>
</fo:static-content>

<fo:static-content flow-name="xsl-region-after">
    <fo:block text-align="right" font-size="10pt">
        Page <fo:page-number/> of <fo:page-number-citation ref-id="last-page"/>
    </fo:block>
</fo:static-content>

renderer.RenderingOptions.HtmlHeader = new HtmlHeaderFooter()
{
    HtmlFragment = "<div style='text-align:center; font-size:10pt;'>Company Name - Confidential</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
};

Imports System

renderer.RenderingOptions.HtmlHeader = New HtmlHeaderFooter() With {
    .HtmlFragment = "<div style='text-align:center; font-size:10pt;'>Company Name - Confidential</div>",
    .DrawDividerLine = True
}

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

// fo.net has very limited PDF security options
// Must use post-processing with another library

' fo.net has very limited PDF security options
' Must use post-processing with another library

using IronPdf;

public byte[] GenerateSecurePdf(string html)
{
    var renderer = new ChromePdfRenderer();
    var pdf = renderer.RenderHtmlAsPdf(html);

    // Set metadata
    pdf.MetaData.Title = "Confidential Report";
    pdf.MetaData.Author = "Company Name";

    // Password protection
    pdf.SecuritySettings.OwnerPassword = "owner123";
    pdf.SecuritySettings.UserPassword = "user456";

    // Restrict permissions
    pdf.SecuritySettings.AllowUserCopyPasteContent = false;
    pdf.SecuritySettings.AllowUserPrinting = IronPdf.Security.PdfPrintSecurity.NoPrint;
    pdf.SecuritySettings.AllowUserEdits = IronPdf.Security.PdfEditSecurity.NoEdit;

    return pdf.BinaryData;
}

Imports IronPdf

Public Function GenerateSecurePdf(html As String) As Byte()
    Dim renderer = New ChromePdfRenderer()
    Dim pdf = renderer.RenderHtmlAsPdf(html)

    ' Set metadata
    pdf.MetaData.Title = "Confidential Report"
    pdf.MetaData.Author = "Company Name"

    ' Password protection
    pdf.SecuritySettings.OwnerPassword = "owner123"
    pdf.SecuritySettings.UserPassword = "user456"

    ' Restrict permissions
    pdf.SecuritySettings.AllowUserCopyPasteContent = False
    pdf.SecuritySettings.AllowUserPrinting = IronPdf.Security.PdfPrintSecurity.NoPrint
    pdf.SecuritySettings.AllowUserEdits = IronPdf.Security.PdfEditSecurity.NoEdit

    Return pdf.BinaryData
End Function

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

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

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

Imports System

' GOOD - Reuse the renderer
Public Class PdfService
    Private Shared ReadOnly _renderer As New ChromePdfRenderer()

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

' BAD - Creating new instance each time
Public Function GenerateBad(html As String) As Byte()
    Dim renderer As New ChromePdfRenderer() ' Wasteful
    Return renderer.RenderHtmlAsPdf(html).BinaryData
End Function

public static class UnitConverter
{
    public static double InchesToMm(double inches) => inches * 25.4;
    public static double PointsToMm(double points) => points * 0.352778;
    public static double PicasToMm(double picas) => picas * 4.233;
    public static double CmToMm(double cm) => cm * 10;
}

// Usage
renderer.RenderingOptions.MarginTop = UnitConverter.InchesToMm(1);  // 1 inch

Public Module UnitConverter
    Public Function InchesToMm(inches As Double) As Double
        Return inches * 25.4
    End Function

    Public Function PointsToMm(points As Double) As Double
        Return points * 0.352778
    End Function

    Public Function PicasToMm(picas As Double) As Double
        Return picas * 4.233
    End Function

    Public Function CmToMm(cm As Double) As Double
        Return cm * 10
    End Function
End Module

' Usage
renderer.RenderingOptions.MarginTop = UnitConverter.InchesToMm(1)  ' 1 inch

// XSL-FO: page-height='11in' page-width='8.5in' (Letter)
renderer.RenderingOptions.PaperSize = PdfPaperSize.Letter;

// XSL-FO: page-height='297mm' page-width='210mm' (A4)
renderer.RenderingOptions.PaperSize = PdfPaperSize.A4;

// Custom size (in mm)
renderer.RenderingOptions.SetCustomPaperSize(210, 297);

' XSL-FO: page-height='11in' page-width='8.5in' (Letter)
renderer.RenderingOptions.PaperSize = PdfPaperSize.Letter

' XSL-FO: page-height='297mm' page-width='210mm' (A4)
renderer.RenderingOptions.PaperSize = PdfPaperSize.A4

' Custom size (in mm)
renderer.RenderingOptions.SetCustomPaperSize(210, 297)

<style>
    @import url('https://fonts.googleapis.com/css2?family=Roboto&display=swap');
    body { font-family: 'Roboto', Arial, sans-serif; }
</style>

renderer.RenderingOptions.HtmlFooter = new HtmlHeaderFooter()
{
    HtmlFragment = "<div style='text-align:center;'>Page {page} of {total-pages}</div>",
    MaxHeight = 15  // mm
};

Imports System

renderer.RenderingOptions.HtmlFooter = New HtmlHeaderFooter() With {
    .HtmlFragment = "<div style='text-align:center;'>Page {page} of {total-pages}</div>",
    .MaxHeight = 15 ' mm
}