Re: How to convert UInt8 array to NSString

FROM : Gary L. Wade
DATE : Wed May 07 21:27:26 2008

No, that's not the same thing.  The method you suggest assumes an exact encoding; the sniffer functions from TextEncodingConverter look at the data to see if it follows the patterns appropriate for a suggested set of encodings and lets you know which one would be the best match.  Typically, such sniffers are best for differentiating DBCS-based characters where there's a sequence like you'd find in Shift-JIS and the like.  Let me know when you find the "Cocoa" way to do this.

>More modern and more Cocoa way? You mean something like this  +
>[NSString stringWithContentsOfFile:usedEncoding:error:] ;-)
>
>«Discussion
>  This method attempts to determine the encoding of the file at path.»
>
>Le 7 mai 08 à 19:33, Gary L. Wade a écrit :
>

>> If you're interested in determining the best encoding match for 
>> text, look at the TextEncodingConverter.h header, which has 
>> functions related to encoding sniffing.  There may be more modern 
>> techniques available, but I had used that almost a decade ago in a 
>> formerly major web browser.  It's not perfect, of course, but it 
>> might be the best solution for your problem.
>>

>>>
>>> On May 6, 2008, at 9:22 PM, Jens Alfke wrote:
>>>

>>>>
>>>> On 6 May '08, at 10:45 AM, Aki Inoue wrote:
>>>>

>>>>> Actually, I don't recommend using CP1252 as the generic fallback
>>>>> encoding like this.
>>>>> The encoding does have gaps, and the handling of those invalid gaps
>>>>> varies between conversion engines.  CF/NSString treat the invalid
>>>>> bytes strictly and return nil encountering those.

>>>>
>>>> I wasn't aware it had gaps — I've never run into them. Where are 
>>>> they?

>>>
>>> <http://en.wikipedia.org/wiki/Windows-1252>
>>>
>>> 5 characters in the 0x80..0x9F range.
>>>

>>>>> So, our recommendation now is to try UTF-8 first; then, try some
>>>>> other encoding deduced from the context (user's localization,
>>>>> intended source/destination of the data, etc).  If all failed,
>>>>> should try MacRoman as the ultimate fallback (the encoding has no
>>>>> gap so never fails).

>>>>
>>>> In the contexts I've been dealing with — data fetched over HTTP from
>>>> random websites — there hasn't been anything deducible from the
>>>> context (assuming the HTTP Content-Type already failed.) In that
>>>> situation MacRoman is not at all a good fallback as almost no Web
>>>> content uses it; CP-1252 or ISO-Latin-1 are the most likely
>>>> fallbacks after UTF-8.

>>>
>>>
>>> I will agree with this if it's web content you're dealing with.
>>> Although, just do a fallback to windows1252.  Lots of site content 
>>> was
>>> authored with that encoding and mistakenly marked as ISO_8859-1.  But
>>> that's a topic for another forum.
>>>

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>