如下 json 数据
{
"movie_detail":
{
"movie_thumbnail_image":"https://bkimg.cdn.bcebos.com/pic/aa18972bd40735fae6cd4657120318b30f2443a7a299?x-bce-process=image/resize,m_lfit,w_440,limit_1/format,f_auto",
"title":"长津湖",
"synopsis":"《长津湖》是由陈凯歌、徐克、林超贤联合执导，吴京、易烊千玺领衔主演，段奕宏、欧豪特别出演，朱亚文、李晨、胡军、韩东君等主演的抗美援朝电影 ，该片于2021年9月30日在中国大陆上映。该片以抗美援朝战争第二次战役中的长津湖战役为背景，讲述了一段波澜壮阔的历史，在极寒严酷环境下，中国人民志愿军东线作战部队凭着钢铁意志和英勇无畏的战斗精神，扭转战场态势，为长津湖战役胜利作出重要贡献的故事。",
"theater":["A影院","B影院","C影院"],
"comments":
[
{"user_name":"user001","rating":"5","comment":"评论1！"},
{"user_name":"user002","rating":"5","comment":"评论2！"},
{"user_name":"user003","rating":"4","comment":"评论3！"}
]
}
}
可以将此 json 数据分为三个模型 MovieDetailDic，MovieDetail，Comment
首先建立一个 struct 类型的 model -> MovieDetailDic 遵循 Decodable 协议，通过 CodingKey 将模型变量和 json 的 key 对应
struct MovieDetailDic: Decodable {
private enum CodingKeys: String, CodingKey {
case movieDetail = "movie_detail"
}
let movieDetail: MovieDetail?
init(from decoder: Decoder) throws {
let values = try decoder.container(keyedBy: CodingKeys.self)
movieDetail = try values.decodeIfPresent(MovieDetail.self, forKey: .movieDetail)
}
}
将 json 数据 “movie_detail” 对应的 value 建立为 MovieDetail 模型。 变量要和 json 的 key 相对应， 变量名可以自定义， 但是要在 CodingKeys 中将变量名和 key 关联起来， 如【case movieThumbnailImage = "movie_thumbnail_image"】， 如果变量名 和 key 相同，可不做处理。
struct MovieDetail: Decodable {
private enum CodingKeys: String, CodingKey {
case movieThumbnailImage = "movie_thumbnail_image"
case title
case synopsis
case theater
case comments
}
let movieThumbnailImage: String?
let title: String?
let synopsis: String?
let theater: [String]?
let comments: [Comment]?
init(from decoder: Decoder) throws {
let values = try decoder.container(keyedBy: CodingKeys.self)
title = try values.decodeIfPresent(String.self, forKey: .title)
movieThumbnailImage = try values.decodeIfPresent(String.self, forKey: .movieThumbnailImage)
synopsis = try values.decodeIfPresent(String.self, forKey: .synopsis)
theater = try values.decodeIfPresent([String].self, forKey: .theater)
comments = try values.decodeIfPresent([Comment].self, forKey: .comments)
}
}
建立 comment 模型
struct Comment: Decodable {
private enum CodingKeys: String, CodingKey {
case userName = "user_name"
case rating
case comment
}
let userName: String?
let rating: String?
let comment: String?
init(from decoder: Decoder) throws {
let values = try decoder.container(keyedBy: CodingKeys.self)
userName = try values.decodeIfPresent(String.self, forKey: .userName)
rating = try values.decodeIfPresent(String.self, forKey: .rating)
comment = try values.decodeIfPresent(String.self, forKey: .comment)
}
}
然后使用 JSONDecoder 解析获得的 data 即可将 json data 转为自定义模型
let dataList = try! JSONDecoder().decode(MovieDetailDic.self, from: data)
