Objective-C如何列出所有可用的编码

Question

在Java中,我可以使用以下代码获得所有可用的编码:

SortedMap<String, Charset> availableCharsets = Charset.availableCharsets();
Vector allEncodes = new Vector();
for (Map.Entry<String, Charset> entry : availableCharsets.entrySet()) {
            allEncodes.add(entry.getKey());
}

然后,我可以读取任何我想要的编码文件:

Reader in = new InputStreamReader(new FileInputStream(aPath), allEncodes.get(0) );

那么,有没有想法如何在Objective-C中实现它

Answer 1

这或多或少是 Java 代码的翻译。您还需要完成代码检查readingError变量。当然，中心点是avaiableStringEncodings静态消息。

  NSMutableArray *arrayOfEncodings = [[NSMutableArray alloc] init];

  const NSStringEncoding *encodings = [NSString availableStringEncodings];
  while (*encodings != 0){
    [arrayOfEncodings addObject:[NSNumber numberWithInt:*encodings]];
    encodings++;
  }

  NSError *readingError = nil;
  NSString yourPath = @"some path you want";
  NSData *data = [[NSData alloc] initWithContentsOfFile:yourPath    options:NSDataReadingUncached error:&readingError];

  NSStringEncoding firstEncoding = (NSStringEncoding) [((NSNumber *) [arrayOfEncodings objectAtIndex:0]) intValue];

  NSString *myString = [[NSString alloc] initWithData:data encoding:firstEncoding];