How to filter a NSArray - ios

Question

Hey i want to filter an NSArray. In this Array is a lot of information like name, town, telephonenumber, and so on. But some towns are twice or three times in the array.
I have property with a town in it.
So i want only those objects from the arry which match with the property.
For example:
in the Array stands:
Frank, New York, 123456
Oliver, New York, 123456
Thomas, Boston, 123456
and when the property is New York i want olny objects 1 and 2.
Does anyone has an idea how i can do it?
This is my code:
NSString *filterString = newsArticle;
NSPredicate *prediacte = [NSPredicate predicateWithFormat:[NSString stringWithFormat:#"Ort == '%#'",filterString]];
newsTownArray = [news filteredArrayUsingPredicate:predicate];
and when i come to the line:
cell.textLabel.text=[[newsTownArray objectAtIndex:indexPath.row] objectForKey:"Name"];

Answer 1

You need to use NSPredicate for this.
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"town == 'New York'"];
[yourArray filterUsingPredicate:predicate];
Dynamically you can create predicate like:
NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:#"town == '%#'",yourInput]];
Here yourInput is a NSString which holds the required town name.
Please check these articles for more details:
codeproject
useyourloaf

Answer 2

Use this code
NSMutableArray *subpredicates = [NSMutableArray array];
for(NSString *term in arryOfWordsToBeSearched) {
NSPredicate *p = [NSPredicate predicateWithFormat:#"self contains[cd] %#",term];
[subpredicates addObject:p];
}
NSPredicate *filter = [NSCompoundPredicate andPredicateWithSubpredicates:subpredicates];
result = (NSMutableArray*)[arryOfDummyData filteredArrayUsingPredicate: filter];

Answer 3

However you can do it within an array with the use of NSPredicate, but I will suggest to do bit differently, this will add up to your code and good programming way.
Create a custom class Person having these properties name, city and telephone.
Create an array that will store objects of Person.
After this you can manipulate/ filter / sort etc quite easily.
NSString *filterCity=#"Delhi";
NSMutableArray *yourArray=[NSMutableArray arrayWithArray:self.persons];
NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:#"city == '%#'",filterCity]];
[yourArray filterUsingPredicate:predicate];
NSLog(#"Filtered");
for (Person *per in yourArray) {
NSLog(#"Name: %#, City: %#, Telephone: %#",per.name, per.city, per.telephone);
}