swift - 如何在 coredata 中同时使用谓词和排序描述符

Question

我正在使用“sortdescriptor”来获取“nsmutablearray”，它按创建日期排序，但问题不是按谓词过滤。我想同时应用排序和过滤器。我已尝试使用以下方法

let fetchRequest = NSFetchRequest<NSManagedObject>(entityName: entityName)
    let sort = NSSortDescriptor(key: "date", ascending: false)
    let pre:NSPredicate = NSPredicate(format: "id == %d", 100)
    fetchRequest.predicate = pre
    fetchRequest.sortDescriptors = [sort]

Answer 1

你可以试试这个:-

change <Message> to your entityModel


let fetchRequest = NSFetchRequest<Message>.init(entityName: "Message")
fetchRequest.sortDescriptors = [NSSortDescriptor.init(key: "date", ascending: false)]
let predicate = NSPredicate.init(format: "id = %@","100")
fetchRequest.predicate = predicate