ios - Form NSPredicate from string that contains id's -

ios - Form NSPredicate from string that contains id's -

i have problem can't think of how write predicate.

i have entity called contact, has string property "pages", let's say

contact.pages = @"1,5,11,15,17";

there lot of contacts in database, , want fetch these contacts contains id. let's want fetch these contacts, pages contains id @"1".

i can think of this,

nspredicate* predicate = [nspredicate predicatewithformat:@"self.pages contains %@", _pageid];

but problem contacts, e.g has pages = @"11,15".

so ideas on how accomplish that? grateful suggestions, in advance!

the "matches" operator of nspredicate can used compare against regular expression:

nsstring *pageid = @"1"; nsstring *regex = [nsstring stringwithformat:@"(.*,)?%@(,.*)?", pageid]; nspredicate *predicate = [nspredicate predicatewithformat:@"pages matches %@", regex];

but should consider replace string property to-many relationship page entity, predicate like

nspredicate *predicate = [nspredicate predicatewithformat:@"any pages.pageid == %@", pageid];

ios objective-c core-data nspredicate nsfetchrequest