如何在Swift中实现decodeObjectOfClasses

Question

我无法找到NSSecureCoding在Swift中符合协议的正确方法,特别是在解码作为其他对象数组的对象时.

我无法NSSet在swift中创建类类型.

在Objective-C中我会使用

self.books = [aDecoder decodeObjectOfClasses:[NSSet setWithObjects:[NSArray class], [Book class], nil] forKey:@"books"];

在Swift我遇到了NSSet这样的问题:

self.books = aDecoder.decodeObjectOfClasses(NSSet().setByAddingObject(NSArray.self).setByAddingObject(Book.self), forKey:"books")

这是错误:

Type 'NSArray.Type' does not conform to protocol 'AnyObject'

Answer 1

对于简单的对象：

self.myObject = aDecoder.decodeObjectOfClass(MyObject.self, forKey: "myObject")!

自 Swift 3.0 起：

self.myObject = aDecoder.decodeObject(of:MyObject.self, forKey: "myObject")!

雨燕4

aDecoder.decodeObject(of: [NSArray.self, Book.self], forKey: "books") as? [Book]

对于嵌套对象：

NSSet(objects: [NSArray.self, Book.self])

Answer 2

宣言

迅速

func decodeObjectOfClasses(_ classes: NSSet,
                    forKey key: String) -> AnyObject?

自 Swift 3.0 起：

func decodeObject<DecodedObjectType where DecodedObjectType : NSCoding, DecodedObjectType : NSObject>(of cls: DecodedObjectType.Type, forKey key: String) -> DecodedObjectType?

目标C

- (id)decodeObjectOfClasses:(NSSet *)classes
                     forKey:(NSString *)key

let books: AnyObject? = aDecoder.decodeObjectOfClasses(NSSet().setByAddingObject(NSArray.self).setByAddingObject(Book.self), forKey:"books")