如何比较NSStrings的两个NSArray,忽略大小写和顺序

Question

我有两个NSArrays,每个包含NSStrings.

如何检查它们是否等效,忽略大小写和顺序？

我一直在玩NSSets和NSPredicates,但没有太多运气.

Answer 1

简单(不区分大小写)

NSSet* one = [[NSCountedSet setWithArray:firstArray] valueForKey:@"lowercaseString"];
NSSet* two = [[NSCountedSet setWithArray:secondArray] valueForKey:@"lowercaseString"];

return [one isEqualToSet:two];

复杂(案例和变音符号不敏感)

此解决方案更复杂,因为它需要特殊的字符串比较.您可以通过使用此方法迭代排序的数组来实现此目的,或者,如果您希望使用valueForKey:,则使用以下代码.

@interface LNComparisonHelper : NSObject

- (instancetype)initWithString:(NSString*)str;
@property (nonatomic, copy, readonly) string;

@end

@implementation LNComparisonHelper

- (instancetype)initWithString:(NSString*)str
{
    self = [super init];
    if(self) { _str = [str copy]; }
    return self;
}

- (BOOL)isEqual:(LNComparisonHelper*)other
{
    return [_str compare:other.string options:(DiacriticInsensitiveSearch | CaseInsensitiveSearch)] == OrderedSame;
}

@end

@interface NSString (ComparisonWrapper)

- (id) ln_casediacriticInsensitiveComparator;

@end

@implementation NSString (ComparisonWrapper)

- (id) ln_casediacriticInsensitiveComparator
{
    return [[LNComparisonHelper alloc] initWithString:self];
}

@end

NSSet* one = [[NSCountedSet setWithArray:firstArray] valueForKey:@"ln_casediacriticInsensitiveComparator"];
NSSet* two = [[NSCountedSet setWithArray:secondArray] valueForKey:@"ln_casediacriticInsensitiveComparator"];

return [one isEqualToSet:two];