using System;
using System.IO;
using System.Text;

namespace SampleConvert
{
    class Class1
    {
        static void Main(string[] args)
        {
            //"Set image folder for properly exporting RTF to HTML string" 
            SautinSoft.RtfToHtml r = new SautinSoft.RtfToHtml();

            //specify some options
            r.OutputFormat = SautinSoft.RtfToHtml.eOutputFormat.XHTML_10;
            r.Encoding = SautinSoft.RtfToHtml.eEncoding.UTF_8;

            //set image options
            r.ImageStyle.ImageFolder = Path.GetDirectoryName(Path.GetFullPath(@"..\..\..\..\..\test.rtf")); //this folder must exist
            r.DestFile = Path.GetFullPath(@"..\..\..\..\..\test.html"); //this folder must exist
            r.ImageStyle.ImageSubFolder = "images";   //this folder will be created by the component, check that folder has write permissions
            r.ImageStyle.ImageFileName = "picture"; //template name for images
            r.ImageStyle.IncludeImageInHtml = false;//false - save images on HDD, true - save images inside HTML
            r.ImageStyle.MakeAbsolutePathToImage = false;

            string rtfFile = @"..\..\..\..\..\test.rtf";
            string htmlFile = @"..\..\..\..\..\test.html";
            string rtfString = null;
            string htmlString = null;
            ReadFromFile(rtfFile,ref rtfString);

            htmlString = r.ConvertString(rtfString);
            if (htmlString != "")
            {
                System.Console.WriteLine("Converted successfully!");
                WriteToFile(htmlFile,htmlString);
                System.Diagnostics.Process.Start(htmlFile);
            }
            else
                System.Console.WriteLine("Converting Error!");
        }

        public static int ReadFromFile(string fileName,ref string fileStr)
        {
            try
            {
                FileInfo fi = new FileInfo(fileName);
                StreamReader strmRead = fi.OpenText();
                fileStr = strmRead.ReadToEnd();
                strmRead.Close();
                return 0;
            }
            catch 
            {
                //error open file
                System.Console.WriteLine("Error in open file");
                return 1;
            }
        }
        public static int WriteToFile(string fileName, string fileStr)
        {
            try
            {
                StreamWriter sw = new StreamWriter(fileName, false);
                sw.Write(fileStr);
                sw.Close();
            }
            catch
            {
                return 2;
            }
            return 0;
        }
    }
}

Imports System
Imports System.IO
Imports System.Text

Module sample

    Sub Main()
        'Set image folder for properly exporting RTF to HTML string
        Dim r As New SautinSoft.RtfToHtml()

        'specify some options
        r.OutputFormat = SautinSoft.RtfToHtml.eOutputFormat.XHTML_10
        r.Encoding = SautinSoft.RtfToHtml.eEncoding.UTF_8

        'set image options
        r.ImageStyle.ImageFolder = Path.GetDirectoryName(Path.GetFullPath("..\..\..\..\test.rtf")) 'this folder must exist
        r.DestFile = Path.GetFullPath("..\..\..\..\test.html") 'this folder must exist
        r.ImageStyle.ImageSubFolder = "images" 'this folder will be created by the component, check that folder has write permissions
        r.ImageStyle.ImageFileName = "picture" 'template name for images
        r.ImageStyle.IncludeImageInHtml = False 'false - save images on HDD, true - save images inside HTML
        r.ImageStyle.MakeAbsolutePathToImage = False

        Dim rtfFile As String = "..\..\..\..\test.rtf"
        Dim htmlFile As String = "..\..\..\..\test.html"
        Dim rtfString As String = Nothing
        Dim htmlString As String = Nothing
        ReadFromFile(rtfFile, rtfString)

        htmlString = r.ConvertString(rtfString)
        If htmlString <> "" Then
            System.Console.WriteLine("Converted successfully!")
            WriteToFile(htmlFile, htmlString)
            System.Diagnostics.Process.Start(htmlFile)
        Else
            System.Console.WriteLine("Converting Error!")
        End If
    End Sub

    Public Function ReadFromFile(ByVal fileName As String, ByRef fileStr As String) As Integer
        Try
            Dim fi As New FileInfo(fileName)
            Dim strmRead As StreamReader = fi.OpenText()
            fileStr = strmRead.ReadToEnd()
            strmRead.Close()
            Return 0
        Catch
            'error open file
            System.Console.WriteLine("Can't open file!")
            Return 1
        End Try
    End Function
    Public Function WriteToFile(ByVal fileName As String, ByVal fileStr As String) As Integer
        Try
            Dim sw As New StreamWriter(fileName, False)
            sw.Write(fileStr)
            sw.Close()
        Catch
            Return 2
        End Try
        Return 0
    End Function
End Module