1. Simple conversion of HTML file to RTF file in C#:

            SautinSoft.HtmlToRtf h = new SautinSoft.HtmlToRtf();

            string inputFile = @"d:\sample.html";
            string outputFile = Path.ChangeExtension(inputFile, ".rtf");

            if (h.OpenHtml(inputFile))
            {
                bool ok = h.ToRtf(outputFile);

                // Open the result for demonstration purposes.
                if (ok)
                    System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(outputFile)
                    { UseShellExecute = true });
            }

2. Convert HTML to RTF in memory using C#; Set page size to Letter/Landscape, add page numbers:

            SautinSoft.HtmlToRtf h = new SautinSoft.HtmlToRtf();

            // Let's set some page options.
            h.PageStyle.PageSize.Letter();
            h.PageStyle.PageOrientation.Landscape();

            h.PageStyle.PageNumbers.Format = "Page {page} of {numpages}";
            h.PageStyle.PageNumbers.AlignH = SautinSoft.HtmlToRtf.eAlign.Center;
            h.PageStyle.PageNumbers.AlignV = SautinSoft.HtmlToRtf.eAlign.Bottom;

            string inputFile = @"d:\utf-8.html";
            string outputFile = Path.ChangeExtension(inputFile, ".rtf");

            // Specify the 'BaseURL' property that component can find the full path to images, like a: <img src="..\pict.png" and
            // to external css, like a:  <link rel="stylesheet" href="/css/style.css" >.
            h.BaseURL = Path.GetFullPath(inputFile);

            using (FileStream htmlFileStream = new FileStream(inputFile, FileMode.Open))
            {
                if (h.OpenHtml(htmlFileStream))
                {
                    using (MemoryStream rtfMemoryStream = new MemoryStream())
                    {
                        bool ok = h.ToRtf(rtfMemoryStream);

                        // Open the result for demonstration purposes.
                        if (ok)
                        {
                            File.WriteAllBytes(outputFile, rtfMemoryStream.ToArray());
                            System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(outputFile)
                            { UseShellExecute = true });
                        }
                    }
                }
            }

3. Convert HTML to RTF in memory using VB.NET; Set page size to Letter/Landscape, add page numbers:

        Dim h As New SautinSoft.HtmlToRtf()

        Dim inputFile As String = "d:\utf-8.html"
        Dim outputFile As String = Path.ChangeExtension(inputFile, ".rtf")

        ' Let's set some page options.
        h.PageStyle.PageSize.Letter()
        h.PageStyle.PageOrientation.Landscape()

        h.PageStyle.PageNumbers.Format = "Page {page} of {numpages}"
        h.PageStyle.PageNumbers.AlignH = SautinSoft.HtmlToRtf.eAlign.Center
        h.PageStyle.PageNumbers.AlignV = SautinSoft.HtmlToRtf.eAlign.Bottom

        ' Specify the 'BaseURL' property that component can find the full path to images, like a: <img src="..\pict.png" and
        ' to external css, like a:  <link rel="stylesheet" href="/css/style.css">.
        h.BaseURL = Path.GetFullPath(inputFile)

        Using htmlFileStream As New FileStream(inputFile, FileMode.Open)
            If h.OpenHtml(htmlFileStream) Then
                Using rtfMemoryStream As New MemoryStream()
                    Dim ok As Boolean = h.ToRtf(rtfMemoryStream)
                    ' Open the result for demonstration purposes.
                    If ok Then
                        File.WriteAllBytes(outputFile, rtfMemoryStream.ToArray())
                        System.Diagnostics.Process.Start(New System.Diagnostics.ProcessStartInfo(outputFile)
                            With { .UseShellExecute = True})
                    End If
                End Using
            End If
        End Using

4. Convert HTML to RTF in C#; Add a custom page header from HTML, add footer from another RTF:

            SautinSoft.HtmlToRtf h = new SautinSoft.HtmlToRtf();
            string inputFile = @"d:\sample.html";
            string outputFile = Path.ChangeExtension(inputFile, ".rtf");

            // Add a header from HTML string.
            h.PageStyle.PageHeader.Html("This is a bold italic line.");

            // Add a footer from RTF file.
            h.PageStyle.PageFooter.FromRtfFile(@"d:\footer.rtf");

            // Make the conversion of HTML to RTF.
            if (h.OpenHtml(inputFile))
            {
                bool ok = h.ToRtf(outputFile);

                // Open the result for demonstration purposes.
                if (ok)
                    System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(outputFile)
                    { UseShellExecute = true });
            }

5. Convert HTML to RTF and extract all images from HTML (local, remote, even embedded within base-64) in C#:

            SautinSoft.HtmlToRtf h = new HtmlToRtf();
            string htmlPath = @"d:\Fathers and Sons.html";
            string htmlString = File.ReadAllText(htmlPath);
            string rtfPath = Path.ChangeExtension(htmlPath, ".rtf");

            List<HtmlToRtf.SautinImage> imgList = new List<HtmlToRtf.SautinImage>();

            h.BaseURL = @"d:\";

            // Convert HTML to and place all images inside imgList.
            h.ConvertString(htmlString, imgList);

            // Save all images to HDD.
            foreach (HtmlToRtf.SautinImage img in imgList)
            {
                img.Img.Save(String.Format(@"d:\{0}.png", img.Cid));
            }

Requires only .NET Framework 4.0 and up or .NET Core 2.0 and up. Our product is compatible with all .NET languages and supports all Operating Systems where .NET Framework and .NET Core can be used.

Note, that «HTML to RTF .Net» is entirely written in managed C#, which makes it absolutely standalone and an independent library.