ios - 如何在swift4中从json数组获取值

Question

我无法将 json 值放入变量中。我正在打印值，但问题是我无法在没有数组的情况下获取 json 值

这是我的 json

{
"Categories": [
    "city",
    "delhi"
   ]
}

我想用数组对值进行分类，并用数组打印值

这是我的代码

do{
            let json = try JSONSerialization.jsonObject(with: data!, options: []) as! [String: AnyObject]
            print(json as AnyObject)

            if let Categories = json["Categories"] {
                print(Categories)
            }

Answer 1

你需要

 do {

     let json = try JSONSerialization.jsonObject(with: data!, options: []) as! [String:[String]]
      let arr1 = json["Categories"]!
      let str1 =  arr1.joined(separator: ":")
       print(str1)
     // or 
      let decoded = try JSONDecoder().decode(Root.self, from: data)
       let str =  decoded.categories.joined(separator: ":")
       print(str)

 } catch {
     print(error)
 }

或使用

struct Root: Codable {
    let categories: [String] 
    enum CodingKeys: String, CodingKey {
        case categories = "Categories"
    }
}