title: Filter an NSArray which contains custom objects
body: <p>I have <code>UISearchBar</code>, <code>UITableView</code>, a web service which returns a <code>NSMutableArray</code> that contain objects like this:</p>
  
  <pre><code>//Food.h
  Food : NSObject { 
      NSString *foodName;
      int idFood;
  }
  
  @property (nonatomic, strong) NSString *foodName;
  </code></pre>
  
  <p>And the array:</p>
  
  <pre><code>Food *food1 = [Food alloc]initWithName:@"samsar" andId:@"1"];
  Food *food2 = [Food alloc] initWithName:@"rusaramar" andId:@"2"];
  
  NSSarray *array = [NSArray arrayWithObjects:food1, food2, nil];
  </code></pre>
  
  <p>How do I filter my array with objects with name beginning with "sa"?</p>