c# - byte[] to string without knowing the coding

I saw this answer, The problem is - so I also need to know what type of encoder to use for getting the correct string - it may be in UTF\UTF8\ANSI.

Here is a example from the immediate window.

Encoding.Unicode.GetString(combinedBuf)
"믯ힿ힩힜힕�"

Encoding.UTF8.GetString(combinedBuf)
"שלום"