我无法从plist键值中解包一个值

如何解决我无法从plist键值中解包一个值

我是新手，我正在尝试将属性从nsDictionary加载到vTitle

var nsDictionary: NSDictionary?
         if let path = Bundle.main.path(forResource: "AppData",ofType: "plist") {
            nsDictionary = NSDictionary(contentsOfFile: path)
         }
let vTitle:String = nsDictionary["LbVacationsTitle"]

当我调试时，我在nsDictionary中看到了正确的键，但是我不能只拆开一个键的值 LbVacationsTitle的类型是字符串

解决方法

取决于您的样式偏好...

var nsDictionary: NSDictionary?
if let path = Bundle.main.path(forResource: "AppData",ofType: "plist") {
    nsDictionary = NSDictionary(contentsOfFile: path)
}
if let dict = nsDictionary {
    let vTitle = dict["LbVacationsTitle"] as? String
    if let vt = vTitle {
        // ...
    }
}

...或...

var nsDictionary: NSDictionary?
if let path = Bundle.main.path(forResource: "AppData",ofType: "plist") {
    nsDictionary = NSDictionary(contentsOfFile: path)
}
guard let dict = nsDictionary else {
    print("Couldn't get a valid dictionary")
    return
}
let vTitle = dict["LbVacationsTitle"] as? String
guard let vt = vTitle else {
    print("Couldn't find a string matching LbVacationsTitle")
    return
}
// ...

,

请不要在Swift中使用NSDictionary API来读取属性列表。

有PropertyListSerialization（甚至还有PropertyListDecoder）

let url = Bundle.main.url(forResource: "AppData",withExtension: "plist")!
let data = try! Data(contentsOf: url)
let dictionary = try! PropertyListSerialization.propertyList(from: data,format: nil) as! [String:Any]
let vTitle = dictionary["LbVacationsTitle"] as! String

由于文件在应用程序捆绑包中是不可变的，因此任何崩溃都表明存在设计错误