在 ObjectiveC 中大写或更改 NSString 的大小写

发布于04月08日

我想知道如何将NSMutableArray中的一个对象中的字符串大写.

NSArray包含索引2处的字符串'April'

有这样简单的事情吗？

viewNoteDateMonth.text  = [[displayDate objectAtIndex:2] capitalized];

推荐答案

给你:

viewNoteDateMonth.text  = [[displayDate objectAtIndex:2] uppercaseString];

Btw:
"april" is lowercase ➔ [NSString lowercaseString]
"APRIL" is UPPERCASE ➔ [NSString uppercaseString]
"April May" is Capitalized/Word Caps ➔ [NSString capitalizedString]
"April may" is Sentence caps ➔ (method missing; see workaround below)

因此，你想要的是"uppercase"，而不是"capitalized".)

至于"句子大写"，人们必须记住，"句子"通常意味着"整个字符串".如果你想要真正的句子，请使用下面的第二种方法，否则使用第一种方法:

@interface NSString ()

- (NSString *)sentenceCapitalizedString; // sentence == entire string
- (NSString *)realSentenceCapitalizedString; // sentence == real sentences

@end

@implementation NSString

- (NSString *)sentenceCapitalizedString {
    if (![self length]) {
        return [NSString string];
    }
    NSString *uppercase = [[self substringToIndex:1] uppercaseString];
    NSString *lowercase = [[self substringFromIndex:1] lowercaseString];
    return [uppercase stringByAppendingString:lowercase];
}

- (NSString *)realSentenceCapitalizedString {
    __block NSMutableString *mutableSelf = [NSMutableString stringWithString:self];
    [self enumerateSubstringsInRange:NSMakeRange(0, [self length])
                             options:NSStringEnumerationBySentences
                          usingBlock:^(NSString *sentence, NSRange sentenceRange, NSRange enclosingRange, BOOL *stop) {
        [mutableSelf replaceCharactersInRange:sentenceRange withString:[sentence sentenceCapitalizedString]];
    }];
    return [NSString stringWithString:mutableSelf]; // or just return mutableSelf.
}

@end