Saving CSV file with degree symbol and ASCII encoded

Question

I have string variable txt. It contains "°" degree symbol. I would like to save string into CSV file ASCII encoded. I use the procedure below But the "°" symbol is converted to "?". Do you have any idea how to save properly degree symbol?

    Public Sub Write_File(ByVal txt As String, ByVal fName As String)

    Try

       Using OutFile As New StreamWriter(fName, False, Text.Encoding.ASCII)
          OutFile.Write(txt)
       End Using

       Me.Write_Log("Succesfully Exported")

    Catch ex As Exception

       Me.Write_Log("Write Error during export")

    End Try
 End Sub

That is not possible of course, ASCII does not have a character code for that glyph. Using Encoding.UTF8 instead. — Hans Passant, Jan 07 '15 at 14:02
Thank You Hans. I found the degree symbol in Extended ASCII Codes under code 167. I am confused. See the [Table]http://www.asciitable.com. — Tomas Paul, Jan 07 '15 at 14:09
"Extended ASCII" is nonsense. That's Encoding.GetEncoding(437). Don't use it, it is not 1981 anymore. — Hans Passant, Jan 07 '15 at 14:15
So I am not able to save CSV in ASCII encoding with "°" symbol anyway? — Tomas Paul, Jan 07 '15 at 14:24

Steven Doggart · Accepted Answer · 2015-01-07T14:46:48.040

Encoding.ASCII is for the standard 7-bit ASCII encoding, which does not contain a degree symbol at all. In order to get a degree symbol in ASCII, you would have to use one of the many 8-bit ASCII encodings. For English, you'd probably be most interested in using the ISO 8859-1 code page, since that's the most standard-ish one there is of the bunch. For instance, instead of using Encoding.ASCII, you could do something like this:

Using OutFile As New StreamWriter(fName, False, Text.Encoding.GetEncoding("iso-8859-1"))
    OutFile.Write(txt)
End Using

For a complete list of available encodings, use the Encoding.GetEncodings method, or look at the list of supported ones in the MSDN documentation.

Of course, none of the various 8-bit ASCII encodings are compatible with each other, so, if you do use that, the degree symbol will be a completely different symbol when viewed on a system that uses a different code page by default. That is precisely why UTF-8 has become the new standard. Usage of 8-bit ASCII is widely discouraged since it is practically unworkable in multi-cultural scenarios. If you can use UTF-8 instead, I would. If you must use ASCII, it's best to stick to the standard 7-bit encoding. If you must use an 8-bit ASCII encoding, please do so sparingly and with full awareness of its drawbacks.

One more thing. You mention the degree symbol as being character 167 (0xA7) in your desired target encoding. If that is the case, you may actually be wanting IBM437 encoding rather than ISO 8859-1. IBM437 is the old code page that was used by default in MS-DOS. If you really need to use that code page, you may have additional trouble for two reasons. As you'll see in the MSDN article, that code page is not well supported in the .NET framework. In my testing, outputting the Unicode string containing the degree symbol using that encoding did not work properly. Therefore, you may find yourself needing to use a byte array to represent the data rather than a String variable (which is Unicode). For instance:

File.WriteAllBytes("Test.txt", {167})

The second problem is that IBM437 is likely not the default code page for your windows OS, so even when it is written to the file as byte value 167, it won't actually look like a degree symbol when you view it in a windows application such as notepad.

very nice explanation (and advice) – Ňɏssa Pøngjǣrdenlarp Jan 07 '15 at 14:32 — Ňɏssa Pøngjǣrdenlarp, Jan 07 '15 at 14:32

Saving CSV file with degree symbol and ASCII encoded

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