Question

我收到错误，例如＆＃34;对成员下标的模糊引用＆＃34;在可能包含数组类型值的字典中，当我尝试访问数组类型值然后获取错误。请检查以下代码。

var occupations = [
"Malcolm": "Captain",
"Kaylee": "Mechanic",
"Layme": ["Engineer", "Docter"] 
] as [String : Any]


occupations["Jayne"] = "Public Relations"
var arrOfLayme = occupations["Layme"] as! Array //getting error here, If I use NSArray instead of array all will work as expacted
print(valueOcc[0])

当我使用NSArray类型时，这个代码就像下面一行一样，我想以纯粹的方式做，不想添加Objective-c。

var arrOfLayme = occupations["Layme"] as! NSArray

Answer 1

试试这个：

var occupations:[String:Any] = [
    "Malcolm": "Captain",
    "Kaylee": "Mechanic",
    "Layme": ["Engineer", "Docter"]
    ]

occupations["Jayne"] = "Public Relations"


var arrOfLayme = occupations["Layme"] as! [String]
print(arrOfLayme)

//More safe
if let arr = occupations["Layme"] as? [String] {
    print(arr)
}

Answer 2

Swift 是一种强类型语言，因此，您无法访问通用容器，就像您在目标C 中使用NSArray一样。< / p>

您需要明确告诉编译器，您希望从字典中检索哪种Array。

执行以下操作：

import Foundation

// Delcare type next to the variable, not at the end
// Makes the code more readable
var occupations: [String : Any] = [
    "Malcolm": "Captain",
    "Kaylee": "Mechanic",
    "Layme": ["Engineer", "Docter"] 
    ]

occupations["Jayne"] = "Public Relations"

// Safe reading
if let arrOfLayme = occupations["Layme"] as? [String] {
    print(arrOfLayme)
}

// Force casting option 1
var arrOfLayme = occupations["Layme"] as! Array<String>

// Force casting option 2
var arrOfLayme2 = occupations["Layme"] as! [String]

得到错误＆＃34;模糊引用成员下标＆＃34;使用Array而不是NSArray时

2 个答案: