arrays - 将自定义对象数组保存在 NSUserDefaults 中

Question

如何将自定义对象数组保存到 NSUserDefauls，例如:

class Settings: NSObject {
   var name: String? = ""
   var addresss: [Address] = [Address]()
   var addressSelectedIndex: Int = 0
   ....
}

class Address: NSObject {
   var street: String? = ""
   var city: String? = ""
   ....
}

我已经向这两个类添加了编码器和解码器。出现错误:

func encodeWithCoder(aCoder: NSCoder) {
   ....
   if let _addresss = self.addresss { // here
      aCoder.encodeObject(_ addresss, forKey: "addresss")
   }
}

Initializer for conditional binding must have Optional type, not '[Address]'

Answer 1

addresss 不是可选属性，您将其初始化为空数组。因此，使用 if let 对此属性进行 nil 检查是没有意义的。

您的编码函数应如下所示:

func encodeWithCoder(aCoder: NSCoder) {
   ....
   aCoder.encodeObject(addresss, forKey: "addresss")
}