Search and Comparison Options - NSCaseInsensitiveSearch
These values represent the options available to many of the string classes’ search and comparison methods.
enum {
NSCaseInsensitiveSearch = 1,
NSLiteralSearch = 2,
NSBackwardsSearch = 4,
NSAnchoredSearch = 8,
NSNumericSearch = 64,
NSDiacriticInsensitiveSearch = 128,
NSWidthInsensitiveSearch = 256,
NSForcedOrderingSearch = 512,
NSRegularExpressionSearch = 1024
};
Constants
NSCaseInsensitiveSearch- A case-insensitive search.
NSLiteralSearch- Exact character-by-character equivalence.
NSBackwardsSearch- Search from end of source string.[NSString NSCaseInsensitiveSearch]
NSAnchoredSearch- Search is limited to start (or end, if
NSBackwardsSearch) of source string. NSNumericSearch- Numbers within strings are compared using numeric value, that is,
Name2.txt<Name7.txt<Name25.txt.This option only applies to compare methods, not find. NSDiacriticInsensitiveSearch- Search ignores diacritic marks.[NSString NSCaseInsensitiveSearch]For example, ‘ö’ is equal to ‘o’.
NSWidthInsensitiveSearch- Search ignores width differences in characters that have full-width and half-width forms, as occurs in East Asian character sets.For example, with this option, the full-width Latin small letter 'a' (Unicode code point U+FF41) is equal to the basic Latin small letter 'a' (Unicode code point U+0061).
NSForcedOrderingSearch- Comparisons are forced to return either
NSOrderedAscendingorNSOrderedDescendingif the strings are equivalent but not strictly equal.This option gives stability when sorting. For example, “aaa” is greater than "AAA” ifNSCaseInsensitiveSearchis specified. NSRegularExpressionSearch- The search string is treated as an ICU-compatible regular expression. If set, no other options can apply except
NSCaseInsensitiveSearchandNSAnchoredSearch. You can use this option only with therangeOfString:...methods andstringByReplacingOccurrencesOfString:withString:options:range:.
Discussion of [NSString NSCaseInsensitiveSearch]
See “Searching, Comparing, and Sorting Strings” for details on the effects of these options.
Example of [NSString NSCaseInsensitiveSearch]
NSArray *array = [NSArray arrayWithObjects:@"éli", @"bob", @"earl", @"allen", @"àli", @"aaron", nil];
NSArray *sorted = [array sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
return [(NSString*)obj1 compare:obj2 options:NSDiacriticInsensitiveSearch|NSCaseInsensitiveSearch];
}];
Example of [NSString NSCaseInsensitiveSearch]
@implementation NSString (YourCategory)
- (NSComparisonResult) compareTheAddressBookWay:(NSString*)iString
{
return [self compare:iString
options:NSCaseInsensitiveSearch|NSDiacriticInsensitiveSearch
range:NSRangeFromString(self)
}
@end
Example of [NSString NSCaseInsensitiveSearch]
NSString *someString = @"Here is my string";
NSRange isRange = [someString rangeOfString:@"is " options:NSCaseInsensitiveSearch];
if(isRange.location == 0) {
//found it...
} else {
NSRange isSpacedRange = [someString rangeOfString:@" is " options:NSCaseInsensitiveSearch];
if(isSpacedRange.location != NSNotFound) {
//found it...
}
}