将Any转换为Optional

您可以通过添加伪协议和使用isfor类型检查来检查可选类型,然后Mirror(..)从可选中提取实际类型值Any:

protocol IsOptional {}
extension Optional : IsOptional {}

/* Detect if any is of type optional */
let any: Any = Optional("123")
var object : AnyObject? = nil
switch any {
case is IsOptional:
    print("is an optional")
    if let (_, a) = Mirror(reflecting: any).children.first {
        object = a as? AnyObject
    }
default:
    print("is not an optional")
} /* Prints "is an optional" */

/* Detect if any2 is of type optional */
let any2: Any = String("123")
switch any2 {
case is IsOptional:
    print("is an optional")
    // ...
default:
    print("is not an optional")
} /* Prints "is not an optional" */

Charlie Monroes自己的最终解决方案非常简洁(+1!).我想我会添加一个补充.

鉴于_XUOptional已经定义了协议并对其进行了Optional类型扩展(如Charlies的回答),您可以any使用可选链接和nil合并运算符处理可选或不在一行中的事件:

let anyOpt: Any = Optional("123")
let anyNotOpt: Any = String("123")
var object: AnyObject?

object = (anyOpt as? _XUOptional)?.objectValue ?? (anyOpt as? AnyObject)
/* anyOpt is Optional(..) and left clause of nil coalescing operator
   returns the unwrapped .objectValue: "123" as 'AnyObject'           */

object = (anyNotOpt as? _XUOptional)?.objectValue ?? (anyNotOpt as? AnyObject)
/* anyNotOpt is not optional and left-most optional chaining of left
   clause returns nil ('anyNotOpt as? _XUOptional' -> nil).
   In that case, right clause will successfully cast the non-optional
   'Any' type to 'AnyObject' (with value "123")                       */