Constants to specify kinds of substrings and styles of enumeration.
typedef NSUInteger NSStringEnumerationOptions;
enum {
NSStringEnumerationByLines = 0,
NSStringEnumerationByParagraphs = 1,
NSStringEnumerationByComposedCharacterSequences = 2,
NSStringEnumerationByWords = 3,
NSStringEnumerationBySentences = 4,
NSStringEnumerationReverse = 1UL << 8,
NSStringEnumerationSubstringNotRequired = 1UL << 9,
NSStringEnumerationLocalized = 1UL << 10
};
Constants
NSStringEnumerationByLines
Enumerates by lines. Equivalent to lineRangeForRange:.
NSStringEnumerationByParagraphs
Enumerates by paragraphs. Equivalent to paragraphRangeForRange:.
NSStringEnumerationByComposedCharacterSequences
Enumerates by composed character sequences. Equivalent torangeOfComposedCharacterSequencesForRange:.
NSStringEnumerationByWords
Enumerates by words.
NSStringEnumerationBySentences
Enumerates by sentences.
[NSString NSStringEnumerationLocalized]
NSStringEnumerationReverse
Causes enumeration to occur from the end of the specified range to the start.
NSStringEnumerationSubstringNotRequired
A way to indicate that the block does not need substring, in which case nil will be passed. This is simply a performance shortcut.
NSStringEnumerationLocalized
Causes the enumeration to occur using user's default locale. This does not make a difference in line, paragraph, or composed character sequence enumeration, but it may for words or sentences.
Discussion of [NSString NSStringEnumerationLocalized]
These options are used with the
enumerateSubstringsInRange:options:usingBlock:
method. Pass in oneNSStringEnumerationBy...
option and combine with any of the remaining enumeration style constants using the C bitwise OR
operator.
Example of [NSString NSStringEnumerationLocalized]
NSString *msg = @"Hi, I am testing. How are you? Wow!! this is the best, and I am happy.";
[msg enumerateSubstringsInRange:NSMakeRange(0, [msg length])
options:NSStringEnumerationBySentences | NSStringEnumerationLocalized
usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop)
{
NSLog(@"Sentence:%@", substring);
// Add each sentence into an array
}];
Example of [NSString NSStringEnumerationLocalized]
[aString enumerateSubstringsInRange:NSMakeRange(0, [aString length])
options:NSStringEnumerationByWords | NSStringEnumerationLocalized
usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop){
if ([substring rangeOfString:@"ll" options:NSCaseInsensitiveSearch].location != NSNotFound)
/* do whatever */;
}];
Example of [NSString NSStringEnumerationLocalized]
NSString *string = @"This is a test. This is only a test.";
NSCountedSet *countedSet = [NSCountedSet new];
[string enumerateSubstringsInRange:NSMakeRange(0, [string length])
options:NSStringEnumerationByWords | NSStringEnumerationLocalized
usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop){
// This block is called once for each word in the string.
[countedSet addObject:substring];
// If you want to ignore case, so that "this" and "This"
// are counted the same, use this line instead to convert
// each word to lowercase first:
// [countedSet addObject:[substring lowercaseString]];
}];
NSLog(@"%@", countedSet);
// Results: 2012-11-13 14:01:10.567 Testing App[35767:fb03]
// <NSCountedSet: 0x885df70> (a [2], only [1], test [2], This [2], is [2])