iOS:自然排序

本文介绍了iOS:自然排序的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我有一个 iOS 应用程序，它使用 Core Data 来保存和检索数据.我如何以自然排序顺序获取按 NSString 类型的字段排序的数据?

I have an app for iOS that uses Core Data to save and retrieve data. How would I fetch data sorted by a field of NSString type in natural sort order?

现在的结果是:

100_title 10_title 1_title

我需要:

1_title 10_title 100_title

推荐答案

您可以使用 localizedStandardCompare: 作为核心数据获取请求的排序描述符中的选择器，例如

You can use localizedStandardCompare: as selector in the sort descriptor for the Core Data fetch request, for example

NSSortDescriptor *titleSort = [[NSSortDescriptor alloc] initWithKey:@"title" ascending:YES selector:@selector(localizedStandardCompare:)]; [fetchRequest setSortDescriptors:[titleSort]];

Swift 3:

let titleSort = NSSortDescriptor(key: "title", ascending: true, selector: #selector(NSString.localizedStandardCompare)) fetchRequest.sortDescriptors = [sortDescriptor]

或更好

let titleSort = NSSortDescriptor(key: #keyPath(Entity.title), ascending: true, selector: #selector(NSString.localizedStandardCompare)) fetchRequest.sortDescriptors = [sortDescriptor]

其中Entity"是 Core Data 托管对象子类的名称.

where "Entity" is the name of the Core Data managed object subclass.