Question

Hello I am creating a simple console application in vb.net in order to convert a file from any type to utf8 but i can’t figure out how this thing works with the encoding. I know that the source file is in Unicode, but when i convert it to a new format i get junk. Any suggestions? i am not sure if my code is correct

this is my code.

Imports System.IO
Imports System.Text

Module Module1
    Sub Main()
        Console.Write("Please give the filepath (example:c:/tesfile.csv):")
        Dim filepath As String = Console.ReadLine()
        Dim sEncoding As String = DetermineFileType(filepath)
        Dim strContents As String
        Dim strEncodedContents As String
        Dim objReader As StreamReader
        Dim ErrInfo As String
        Dim bString As Byte()
        Try

            'Read the file
            objReader = New StreamReader(filepath)
            'Read untill the end
            strContents = objReader.ReadToEnd()
            'Close The file
            objReader.Close()
            'Write Contents on DOS
            Console.WriteLine(strContents)
            Console.WriteLine("")

            bString = EncodeString(strContents, "UTF-8")
            strEncodedContents = System.Text.Encoding.UTF8.GetString(bString)
            Dim objWriter As New System.IO.StreamWriter(filepath.Replace(".csv", "_encoded.csv"))
            objWriter.WriteLine(strEncodedContents)
            objWriter.Close()
            Console.WriteLine("Encoding Finished")

        Catch Ex As Exception
            ErrInfo = Ex.Message
            Console.WriteLine(ErrInfo)
        End Try        
        Console.ReadKey()
    End Sub

    Public Function DetermineFileType(ByVal aFileName As String) As String
        Dim sEncoding As String = String.Empty

        Dim oSR As New StreamReader(aFileName, True)
        oSR.ReadToEnd()
        ' Add this line to read the file.
        sEncoding = oSR.CurrentEncoding.EncodingName

        Return sEncoding
    End Function

    Function EncodeString(ByRef SourceData As String, ByRef CharSet As String) As Byte()
        'get a byte pointer To the source data
        Dim bSourceData As Byte() = System.Text.Encoding.Unicode.GetBytes(SourceData)

        'get destination encoding 
        Dim OutEncoding As System.Text.Encoding = System.Text.Encoding.GetEncoding(CharSet)

        'Encode the data To destination code page/charset
        Return System.Text.Encoding.Convert(OutEncoding, System.Text.Encoding.UTF8, bSourceData)
    End Function
End Module

Answer 1

StreamReader has a constructor that takes an Encoding if you know the encoding of the file you should pass that into the constructor of StreamReader

objReader = New StreamReader(filepath, Encoding.UTF32)

EDIT

You say in a comment that the file is Encoded as UCS-2 from Wikipedia

The older UCS-2 (2-byte Universal Character Set) is a similar
character encoding that was superseded by UTF-16 in version 2.0 of the
Unicode standard in July 1996.2 It produces a fixed-length format by
simply using the code point as the 16-bit code unit and produces
exactly the same result as UTF-16 for 96.9% of all the code points in
the range 0-0xFFFF, including all characters that had been assigned a
value at that time.

In which case you can try to decode using UTF-16 which is called Unicode with in System.Text.Encoding so try

objReader = New StreamReader(filepath, Encoding.Unicode)

FYI
Unicode is a standard which has a variety of encodings including

• UTF-8
• UTF-16 (BigEndian)
• UTF-16 (LittleEndian)
• UTF-32 (BigEndian)
• UTF-32 (LittleEndian)

For Microsoft to call UTF-16 Unicode is a little misleading but not inaccurate, UTF-16 is one encoding possible for Unicode.