用unichar追加字符串

Question

我这里有一些奇怪的问题。代码如下

NSMutableString *unicodeString = [NSMutableString string];
for (NSUInteger i = 0; i < [data length]; i++) {
    unsigned char byte;
    [data getBytes:&byte range:NSMakeRange(i, 1)];
    unichar unicodeChar = byte;
    NSString *appendString = [NSString stringWithFormat:@"%C",[_toUnicode unicharFromCIDString:unicodeChar]];
    [unicodeString appendFormat:@"%@",appendString];
    NSLog(@"%@",appendString); //1
}
NSLog(@"%@",unicodeString)//2 

打印appendString，但unicodeString从不打印。这是因为字节问题吗??我已经尝试保留appendString，但它仍然不会打印

*UPDATED找到答案

Answer 1

换句话说:

NSString *appendString = [NSString stringWithCharacters:&unicodeChar length:1];
[unicodeString appendFormat:@"%@", appendString];

Answer 2

我发现问题是%C是16位单字符，所以如果我想追加到NSString，我必须使用%C，这是8位。

NSString *appendString = [NSString stringWithFormat:@"%c",[_toUnicode     unicharFromCIDString:unicodeChar]];
[unicodeString appendFormat:@"%@",appendString];