nspredicate iphone question

Question

i have the following code

NSPredicate* predicate = [NSPredicate predicateWithFormat:@"Word== %@", randomWord];
rows = [[courseArray filteredArrayUsingPredicate:predicate]retain];

I am using this in a search bar. I have two questions - how can i make the NSPredicate so it takes every word that begins with the characters typed rather than having a value equal another? e.g I have "Men, Many,Morons, Now,Never" in the array, and when i type "M" i want "Men,Many,Morons" to be added. Furthermore, how can i predicate more than 1 value? so it compares between two formats?

thanks...

Answer 1

You need create all of the predicate which you want to compare and append all predicate to array. after that you can use NSCompoundPredicate for or,and condition.

like that

NSPredicate *finalPredicate = [NSCompoundPredicate andPredicateWithSubpredicates:@[[NSPredicate predicateWithFormat:@"is_neutered = 0"],
    [NSCompoundPredicate orPredicateWithSubPredicates:feedDays]]];

Answer 2

The NSPredicate documentation is a good place to start.

The predicate to check if the string begins with another is [NSPredicate predicateWithFormat:@"Word BEGINSWITH %@"]

And as far as checking two predicates, you're looking for NSCompoundPredicate.

Answer 3

Try NSPredicate *predicate = [NSPredicate predicateWithFormat:@"Word BEGINSWITH %@", randomWord];

If you want to search the whole word you can try CONTAINS..

Answer 4

http://developer.apple.com/library/ios/#documentation/Cocoa/Conceptual/Predicates/Articles/pCreating.html

Look for the 'Prefix' part under the String Constants, Variables, and Wildcards section.