Extended Ascii problem

Question

Hello folks,
I have a problem to convert extended ascii to unicode. For example char 'œ' (decimal value 156) is in Ascii table but that is defferent in unicode table with value 339.

Therefore, in C#, Request.BinaryRead(byteCount); is reading 'œ' char with ascii value 156 but when it decode it with System.Convert.ToChar(btyValue[i]) function or other function, it is searching unicode table and there is no char with value 156 in unicode.

Is there any function that can do this convertion? that means, 'œ'has different ascii value (156) and unicode value (339), but i will encode and decode the char and get the same char.

Thanks in Advance.
Shuvra