Swift 3 中的动态类型

Question

我已经将我的 swift 版本从 2.3 迁移到 3，它自动转换了一些代码，下面是我崩溃的情况我已经尝试了一些选项但徒劳无功，

swift 2.3:工作正常

public func huntSuperviewWithClassName(className: String) -> UIView?
{
    var foundView: UIView? = nil

    var currentVeiw:UIView? = self

    while currentVeiw?.superview != nil{
        if let classString = String.fromCString(class_getName(currentVeiw?.dynamicType)){

            if let classNameWithoutPackage = classString.componentsSeparatedByString(".").last{
                print(classNameWithoutPackage)
                if classNameWithoutPackage == className{
                    foundView = currentVeiw
                    break
                }
            }
        }
        currentVeiw = currentVeiw?.superview
    }

    return foundView
}

}

swift3:Not很好

  if let classString = String(validatingUTF8: class_getName(type(of:currentVeiw) as! AnyClass)) {

也试过这一行：

  if let classString = String(describing: class_getName(type(of: currentVeiw) as! AnyClass)){

但它不起作用..

请指导我如何根据 swift 3:

更正此行

 if let classString = String.fromCString(class_getName(currentVeiw?.dynamicType)){

Answer 1

if let classString = String(describing: currentVeiw.self) 
{
}

Answer 2

尝试以下操作：

public func huntSuperviewWithClassName(className: String) -> UIView?
{
    var foundView: UIView? = nil
    var currentVeiw:UIView? = self
    while currentVeiw?.superview != nil{
        let classString = String(describing: type(of: currentVeiw?.classForCoder))
        if let classNameWithoutPackage = classString.components(separatedBy:".").first {
            print(classNameWithoutPackage)
            if classNameWithoutPackage == className {
                foundView = currentVeiw
                break
            }
        }
        currentVeiw = currentVeiw?.superview
    }
    return foundView
}

Answer 3

只需这样做：

let classString = String(describing: type(of: currentVeiw!))

Answer 4

编译器告诉您不能使用 if let，因为它完全没有必要。您没有任何可选项要解包。if let 专门用于解包选项。

public func huntSuperviewWithClassName(className: String) -> UIView?
{
    var foundView: UIView? = nil

    var currentVeiw:UIView? = self

    while currentVeiw?.superview != nil{

            let classString = NSStringFromClass((currentVeiw?.classForCoder)!)

            if let classNameWithoutPackage = classString.components(separatedBy:".").last{
                print(classNameWithoutPackage)
                if classNameWithoutPackage == className{
                    foundView = currentVeiw
                    break
                }
            }
        }
        currentVeiw = currentVeiw?.superview
    }

    return foundView
}

工作正常！

Swift 3 中的动态类型

Dynamic Type in Swift 3

ios

dynamictype

swift3

swift2.3