Determine if a text file without BOM is UTF8 or ASCII VB.NET

Question

I'm using VB.NET 2008.

 Dim oEncoding As Encoding
 Dim oReader As StreamReader
 Dim sReadString As String

 oReader = New StreamReader("TextNonBOM.txt", System.Text.Encoding.Default, True)
 sReadString = oReader.ReadToEnd().ToLower()
 oEncoding = oReader.CurrentEncoding
 oReader.Close()

Without BOM is UTF8 or ASCII?

Answer 1

If your only choices are UTF-8 and ASCII, you don't have to detect anything. All ASCII is valid UTF-8, so you can always decode as UTF-8.