NSSortDescriptor在Swift中使用NSDate进行排序

Question

我如何使用托管对象的date属性对NSFetchRequest进行排序.那么它创建一个日期按顺序排列的数组？

这是我到目前为止的代码......

    var request : NSFetchRequest = NSFetchRequest(entityName: "History");
    request.predicate = NSPredicate(format: "counts = %@", true)
    request.sortDescriptors = [???] <- What should I put here?
    var results : [NSManagedObject] = context.executeFetchRequest(request, error: nil) as [NSManagedObject]

Answer 1

// newest first
request.sortDescriptors = [NSSortDescriptor(key: "date", ascending: false)]

注意: : [NSManagedObject] 如果您已经拥有,则 不需要as [NSManagedObject].使用工厂方法时
不需要 .: NSFetchRequest NSFetchRequest