ios - 如何获取数组中的字典对象

Question

我有一个包含以下数据的 dict(NSDictionary)。

{
    images =     (
                {
            image = "image.jpg";
            scores =             (
                                {
                    "classifier_id" = "Adventure_Sport";
                    name = "Adventure_Sport";
                    score = "0.662678";
                },
                                {
                    "classifier_id" = Climbing;
                    name = Climbing;
                    score = "0.639987";
                },
                                {
                    "classifier_id" = Flower;
                    name = Flower;
                    score = "0.628092";
                },
                                {
                    "classifier_id" = "Nature_Scene";
                    name = "Nature_Scene";
                    score = "0.627548";
                },
                                {
                    "classifier_id" = Icicles;
                    name = Icicles;
                    score = "0.617094";
                },
                                {
                    "classifier_id" = Volcano;
                    name = Volcano;
                    score = "0.604928";
                },
                                {
                    "classifier_id" = Potatoes;
                    name = Potatoes;
                    score = "0.602799";
                },
                                {
                    "classifier_id" = "Engine_Room";
                    name = "Engine_Room";
                    score = "0.595812";
                },
                                {
                    "classifier_id" = Bobsledding;
                    name = Bobsledding;
                    score = "0.592521";
                },
                                {
                    "classifier_id" = White;
                    name = White;
                    score = "0.587923";
                },
                                {
                    "classifier_id" = Yellow;
                    name = Yellow;
                    score = "0.574398";
                },
                                {
                    "classifier_id" = "Natural_Activity";
                    name = "Natural_Activity";
                    score = "0.54574";
                },
                                {
                    "classifier_id" = Butterfly;
                    name = Butterfly;
                    score = "0.526803";
                },
                                {
                    "classifier_id" = "Dish_Washer";
                    name = "Dish_Washer";
                    score = "0.513662";
                },
                                {
                    "classifier_id" = Rainbow;
                    name = Rainbow;
                    score = "0.511032";
                }
            );
        }
    );
}

我想不出一种方法来访问数组中的 classfier_id

真的需要你的帮助。谢谢。 PS 我已经尝试过 dict["scores"] 和 dict["image.scores"]

请帮助..谢谢

Answer 1

你想要

let classifier_ids = dict["scores"].map{$0["classifier_id"]}

如果您的容器是 NSObject 而不是 Swift 字典和数组，那么您将需要添加一些类型转换，但这是基本思想。

此代码对于非类型化集合会更安全:

var classifier_ids: [String?]
if let array = dict["scores"] as? [String:String]
{
  let classifier_ids = array.map{$0["classifier_id"]}
}

这应该给你一个可选数组，如果数组中的给定条目不包含“classifier_id”键/值对，则给定条目将为 nil。

或者，如果您想跳过不包含“classifier_id”键/值对的条目:

var classifier_ids: [String]
if let array = dict["scores"] as? [String:String]
{
  let classifier_ids = array.flatmap{$0["classifier_id"]}
}