Swift:参数类型'[String:ValueType]'不符合预期类型'AnyObject'

Question

我有以下代码尝试将字典转换为NSData:

func dataFromDict<ValueType>(dict: [String:ValueType]) -> NSData {
    return NSKeyedArchiver.archivedDataWithRootObject(dict)
}

编译器给我这个错误dict作为参数传递:

Argument type '[String:ValueType]' does not conform to expected type 'AnyObject'

编辑:

@ vadian的解决方案对我有用.

我还试图将这个词组投射到NSDictionary:

return NSKeyedArchiver.archivedDataWithRootObject(dict as NSDictionary)

但是得到这个错误:

Cannot convert value of type '[String:ValueType]' to type 'NSDictionary' in coercion

为什么？

Answer 1

因为archivedDataWithRootObject期望AnyObject只是投射字典

func dataFromDict<ValueType>(dict: [String:ValueType]) -> NSData {
  return NSKeyedArchiver.archivedDataWithRootObject(dict as! AnyObject)
}