我们可以重载MVC控制器动作方法吗？

Question

我试图重载控制器方法或操作我能够编写控制器操作并编译但仍然没有得到结果。

extension String {
    func stringByAppendingPathComponent1(path: String) -> String {
        let nsSt = self as NSString
        return nsSt.appendingPathComponent(path)
    }
}

let writePath = NSTemporaryDirectory().stringByAppendingPathComponent(path: "instagram.igo")


extension String {

    var lastPathComponent: String {
        return (self as NSString).lastPathComponent
    }
    var pathExtension: String {
        return (self as NSString).pathExtension
    }
    var stringByDeletingLastPathComponent: String {
        return (self as NSString).deletingLastPathComponent
    }
    var stringByDeletingPathExtension: String {
        return (self as NSString).deletingPathExtension
    }
    var pathComponents: [String] {
        return (self as NSString).pathComponents
    }
    func stringByAppendingPathComponent(path: String) -> String {
        let nsSt = self as NSString
        return nsSt.appendingPathComponent(path)
    }
    func stringByAppendingPathExtension(ext: String) -> String? {
        let nsSt = self as NSString
        return nsSt.appendingPathExtension(ext)
    }
}

但我仍然得到以下错误 '/'应用程序中的服务器错误