如何按整数属性对CoreData对象数组进行排序？

Question

I have an array of CoreData objects, each object is Person and each Person has an age attribute which is of type Integer32.

My array is filled with Person objects. I want to sort my array by their age attribute.

How can I do this?

Answer 1

It should be as simple as:

NSArray *sortDescriptors = @[
  [NSSortDescriptor sortDescriptorWithKey:@"age" ascending:YES]
];

NSArray *sortedPeople = [people sortedArrayUsingDescriptors:sortDescriptors];
NSLog(@"%@", sortedPeople);

This will work regardless of whether you do or do not choose to "Use scalar properties for primitive data types" when creating your NSManagedObject subclass (if you decide to even create them)

Answer 2

Say "people" is your array of Person objects you want sorted...

NSArray *sortedPeople = [people sortedArrayUsingComparator:^NSComparisonResult(Person *p1, Person *p2) {
    if (p1.age > p2.age) return NSOrderedDescending;
    else if (p1.age < p2.age) return NSOrderedAscending;
    else return NSOrderedSame;
}