Objective C read file wrong encoding - iphone

Question

Hi all I have a problem when I download file from internet from which I need to mine some data. I open it and try to buffer it, but it gives me wrong chars because this file is in Czech...
My code:
- (void) sync {
NSString * path = #"/Users/syky/Documents/stats.csv";
NSFileHandle * fileHandle = [NSFileHandle fileHandleForReadingAtPath:path];
NSData * buffer = nil;
while ((buffer = [fileHandle readDataOfLength:1024])) {
//do something with the buffer
NSString * s = [[NSString alloc]initWithData:buffer encoding:nil];
NSLog(s);
break;
}
No matter which encoding I choose I always get broken chars such as
"Poø.";"Jméno"
I need to get:
"Příjmení";"Jméno"
This file is originaly generated by Microsoft Excel such as *.csv export file...
When I try to open this file by any MAC OS X Text editor I get broken chars as well, but when I open it on other Windows based maschine with Microsoft Excel it works just fine...
Thank you for your help
Solution:
- (void) sync {
NSString * path = #"/Users/syky/Documents/stats.csv";
NSFileHandle * fileHandle = [NSFileHandle fileHandleForReadingAtPath:path];
NSData * buffer = nil;
while ((buffer = [fileHandle readDataOfLength:1024])) {
NSStringEncoding encoding = CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingWindowsLatin2);
NSString *string = [[NSString alloc] initWithData:buffer encoding:encoding];
NSLog(string);
break;
}

Answer 1

First, I'm not a Czech speaker. Second, I think "use UTF-8" is akin to saying "throw a barrel at it." It's heavy-handed in the same way.
From what I've researched, you could use ISO Latin 2 or Apple's Central European Roman encoding. You'll find the former represented among NSStringEncodings, but not the latter, so look to Core Foundation's support:
NSStringEncoding encoding = CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingMacCentralEurRoman);
NSString *string = [[NSString alloc] initWithData:buffer encoding:encoding];
Otherwise, you could (and probably already have, from what you've said) use:
NSString *string = [[NSString alloc] initWithData:buffer encoding:NSISOLatin2StringEncoding];
I'm really curious to see if using CFStringEncoding encodings improves your situation.
EDIT:
If your source was generated by Microsoft Excel, perhaps kCFStringEncodingWindowsLatin2 will work instead of kCFStringEncodingMacCentralEurRoman. Like before, you'll need to convert it using CFStringConvertEncodingToNSStringEncoding.
There's one other approach you might want to try. Since CFStringRef is "toll-bridged" to NSString (and so is CFDataRef to NSData), perhaps working entirely in Core Foundation might work:
CFStringRef stringRef = CFStringCreateFromExternalRepresentation(kCFAllocatorDefault, (CFDataRef)buffer, kCFStringEncodingMacCentralEurRoman);
NSString *string = (NSString *)stringRef;
In this case, don't forget that stringRef has to be released.
Good luck to you in your endeavors.