尝试在 userDefaults 中存储 Int，arrayof [string] 对时出错

Question

self.fetchMin(forStartDate: start, toEndDate: end) { (min, chal) in

    guard let mins = min, let challenges = chal else {
        return
    }

    let dict: [Int : [String]]  = [mins:challenges]

    UserDefaults.standard.set(dict, forKey: "WeekStates")

}

嗨，在上面的程序中，我试图在 userDefaults 中存储键和数组对字符串，但是如果我这样做，它会意外崩溃。

如果我尝试使用一个值，它会起作用。

例如：

`let dict: [String]  =  challenges
 UserDefaults.standard.set(dict, forKey: "WeekStates")

Answer 1

正如你最后提到的那样，我试过 [String] 它有效。

我不确定你是否可以存储 [Int : [String]] 类型的数据，据我所知 UserDefaults 属性列表只能接受某些类型的变量，所以它有那个限制。您可以存储这些类型的变量：

Array
Data
Date
Dictionary
NSNumber
String

Answer 2

https://developer.apple.com/documentation/foundation/userdefaults

The UserDefaults class provides convenience methods for accessing common types such as floats, doubles, integers, Booleans, and URLs. A default object must be a property list—that is, an instance of (or for collections, a combination of instances of): NSData , NSString , NSNumber , NSDate , NSArray , or NSDictionary . If you want to store any other type of object, you should typically archive it to create an instance of NSData. For more details, see Preferences and Settings Programming Guide.

你可以这样做。

let dict: [Int : [String]]  = [1:["iOS Dev"]]

    UserDefaults.standard.set(NSKeyedArchiver.archivedData(withRootObject: dict as NSDictionary) as NSData, forKey: "4WeekStates")

    if let unarchivedObject = UserDefaults.standard.object(forKey: "4WeekStates") as? Data {

        let dic = NSKeyedUnarchiver.unarchiveObject(with: unarchivedObject as Data) as? NSDictionary
        print(dic!)
    }

尝试在 userDefaults 中存储 Int，arrayof [string] 对时出错

Getting error while trying to store Int, arrayof [string] pair in userDefaults

ios

swift3

nsuserdefaults