Change encoding of a string - C#

Essentially the process it to convert the original string into an array of bytes and the convert the array of bytes back into a string using the encoding you want. To do this you use the Encoding class, there is an example of what you are doing here[^] (near the bottom), except that it is taking ASCII and outputting UTF-8. The princple is the same though.

Note that to use this on a stream you will need to buffer, but the process is much simpler as you already have the encoded byte array from the input buffer and the Encode method returns a byte array for your output buffer

[Edit]
By looking at the comments (below) it look like the OP is having problems with html encoding. This can be decoded using this[^]