objective-c - 在 Objective-C 中大写或更改 NSString 的大小写

Question

我想知道如何将在NSMutableArray.

An包含索引 2 处NSArray的字符串。 我希望将其更改为.'April'
'APRIL'

有这样简单的事情吗？

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

Answer 1

给你：

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

顺便说一句：
"april"is lowercase➔ [NSString lowercaseString]
"APRIL" is UPPERCASE➔ [NSString uppercaseString]
"April May" is Capitalized/Word Caps➔ [NSString capitalizedString]
"April may" is Sentence caps➔ （缺少方法；请参阅下面的解决方法）

因此，您想要的是“大写”，而不是“大写”。;)

至于“句子大写”，必须记住，“句子”通常意味着“整个字符串”。如果您希望获得真正的句子，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

Answer 2

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

文档：http: //developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSString_Class/Reference/NSString.html#//apple_ref/occ/instm/NSString/uppercaseString

您还可以使用小写字符串和大写字符串

Answer 3

如果有人在 swift 中需要上述内容：

SWIFT 3.0 及以上版本：

这将使您的字符串大写，使第一个字母大写：

viewNoteDateMonth.text  = yourString.capitalized

这将使您的字符串大写，使所有字符串大写：

viewNoteDateMonth.text  = yourString.uppercased()