What encoding to use with raw bytes in a NSString

I need to store some raw bytes from NSData object into an NSString (basically a null encoding) but I am not sure how to do this. Obviously assigning an improper 8-开发者_运维知识库bit encoding would be bad. NSASCIIStringEncoding is not OK because the docs say "Strict 7-bit ASCII encoding within 8-bit chars; ASCII values 0…127 only." but I need full range of 0x0 - 0xFF.

Base64 encoding is NOT an acceptable solution.

Basically, you don't.

An NSString is for strings of validly encoded string data; typically UTF8 or UTF16. NSData is for arbitrary binary data.

If you want to store raw bytes into an NSString, you need to encode them and base64 is one of the most common means of doing so.

Use NSNEXTSTEPStringEncoding. According to the documentation:

8-bit ASCII encoding with NEXTSTEP extensions.

It appears in the current documentation (as of writing this post) and is available in both Apple and GNU's implementation of the (OPENSTEP) standard.

Caveat: It doesn't state what exactly those "extensions" are, so tread lightly.