Check if String contains any String from array

Question

I know I can check if a string contains another string like this

NSString *string = @\"hello bla bla\";
if ([string rangeOfString:@\"bla\"].location == NSNotFoun         


        

Answer 1

You could use a NSCompoundPredicate

NSCompoundPredicate *predicate = [NSCompoundPredicate orPredicateWithSubpredicates:subPredicates];

Where your subPredicates must look like

(
    SELF CONTAINS[c] "one",
    SELF CONTAINS[c] "two",
    SELF CONTAINS[c] "three",
    SELF CONTAINS[c] "four"
)

To get there from

NSArray *array = @[@"one", @"two", @"three", @"four"]

You could use a for loop, but as you are opposed to that, let's cheat:

by using a category I each NSArray functional mapping, but instead of looping, I use enumerating

@interface NSArray (Map)
-(NSArray *) vs_map:(id(^)(id obj))mapper;
@end

@implementation NSArray (Map)

-(NSArray *)vs_map:(id (^)(id))mapper
{
    NSMutableArray *mArray = [@[] mutableCopy];
    [self enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {

        id mapped = mapper(obj);
        [mArray addObject:mapped];
    }];

    return [mArray copy];
}

@end

Now I can create the subPredicates like

NSArray *subPredicates = [arary vs_map:^id(NSString *obj) {
        return [NSPredicate predicateWithFormat:@"SELF contains[c] %@", obj];
}];

and create the compound predicate like

NSCompoundPredicate *predicate = [NSCompoundPredicate orPredicateWithSubpredicates:subPredicates];

and use it

BOOL doesContain = [predicate evaluateWithObject:string];

et voilà: No (obvious) looping_{, while there is one hidden in the enumeration and probably in the predicate as-well.}

---

Now with the changed question you basically ask for filtering. You can use the same predicate for that:

NSArray *testarray = @[@"I have one head", @"I have two feet", @"I have five fingers"];
NSArray *arary = @[@"one",@"two", @"three", @"four"];

NSArray *subPredicates = [arary vs_map:^id(NSString *obj) {
    return [NSPredicate predicateWithFormat:@"SELF contains[c] %@", obj];
}];

NSCompoundPredicate *predicate = [NSCompoundPredicate orPredicateWithSubpredicates:subPredicates];
NSArray *results = [testarray filteredArrayUsingPredicate:predicate];

results now contains

(
    I have one head,
    I have two feet
)

---

the complete code

#import 

@interface NSArray (Map)
-(NSArray *) vs_map:(id(^)(id obj))mapper;
@end

@implementation NSArray (Map)

-(NSArray *)vs_map:(id (^)(id))mapper
{
    NSMutableArray *mArray = [@[] mutableCopy];
    [self enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {

        id mapped = mapper(obj);
        [mArray addObject:mapped];
    }];

    return [mArray copy];
}

@end


int main(int argc, const char * argv[]) {
    @autoreleasepool {


        NSArray *testarray = @[@"I have one head", @"I have two feet", @"I have five fingers"];
        NSArray *arary = @[@"one",@"two", @"three", @"four"];

        NSArray *subPredicates = [arary vs_map:^id(NSString *obj) {
            return [NSPredicate predicateWithFormat:@"SELF contains[c] %@", obj];
        }];

        NSCompoundPredicate *predicate = [NSCompoundPredicate orPredicateWithSubpredicates:subPredicates];
        NSArray *results = [testarray filteredArrayUsingPredicate:predicate];

    }
    return 0;
}