【发布时间】：2021-03-26 00:39:08
【问题描述】：
我正在尝试从 Unsplash API 解码此 json，但 ContentView 显示为空白，如果我打印结果，则会收到“No value associated with key CodingKeys”错误。这很奇怪，因为我正在关注这个非常新的教程https://www.youtube.com/watch?v=CmOe9vNopjU。我很困惑，因为这应该很简单，但我是 Swift 新手。
这是完整的错误
"No value associated with key CodingKeys(stringValue: \"total\", intValue: nil) (\"total\").", underlyingError: nil))
这里是解码请求
class SearchObjectController : ObservableObject {
static let shared = SearchObjectController()
private init() {}
var token = "my client id"
@Published var results = [Result]()
@Published var searchText : String = "Forest"
func search () {
let url = URL(string: "https://api.unsplash.com/search/photos?query=\(searchText)")
var request = URLRequest(url: url!)
request.httpMethod = "GET"
request.setValue("Client-ID\(token)", forHTTPHeaderField: "Authorization")
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
guard let data = data else {return}
do {
let res = try JSONDecoder().decode(Results.self, from: data)
self.results.append(contentsOf: res.results)
print(self.results)
} catch {
print(error)
}
}
task.resume()
}
}
这些是我为该请求创建的结构
struct Results : Codable {
var total : Int
var results : [Result]
}
struct Result : Codable {
var id : String
var description : String?
var urls : URLs
}
struct URLs : Codable {
var small : String
}
Unplash API Requests 的 json 格式如下所示
{
"total": 133,
"total_pages": 7,
"results": [
{
"id": "eOLpJytrbsQ",
"created_at": "2014-11-18T14:35:36-05:00",
"width": 4000,
"height": 3000,
"color": "#A7A2A1",
"blur_hash": "LaLXMa9Fx[D%~q%MtQM|kDRjtRIU",
"likes": 286,
"liked_by_user": false,
"description": "A man drinking a coffee.",
"user": {
"id": "Ul0QVz12Goo",
"username": "ugmonk",
"name": "Jeff Sheldon",
"first_name": "Jeff",
"last_name": "Sheldon",
"instagram_username": "instantgrammer",
"twitter_username": "ugmonk",
"portfolio_url": "http://ugmonk.com/",
"profile_image": {
"small": "https://images.unsplash.com/profile-1441298803695-accd94000cac?ixlib=rb-0.3.5&q=80&fm=jpg&crop=faces&cs=tinysrgb&fit=crop&h=32&w=32&s=7cfe3b93750cb0c93e2f7caec08b5a41",
"medium": "https://images.unsplash.com/profile-1441298803695-accd94000cac?ixlib=rb-0.3.5&q=80&fm=jpg&crop=faces&cs=tinysrgb&fit=crop&h=64&w=64&s=5a9dc749c43ce5bd60870b129a40902f",
"large": "https://images.unsplash.com/profile-1441298803695-accd94000cac?ixlib=rb-0.3.5&q=80&fm=jpg&crop=faces&cs=tinysrgb&fit=crop&h=128&w=128&s=32085a077889586df88bfbe406692202"
},
"links": {
"self": "https://api.unsplash.com/users/ugmonk",
"html": "http://unsplash.com/@ugmonk",
"photos": "https://api.unsplash.com/users/ugmonk/photos",
"likes": "https://api.unsplash.com/users/ugmonk/likes"
}
},
"current_user_collections": [],
"urls": {
"raw": "https://images.unsplash.com/photo-1416339306562-f3d12fefd36f",
"full": "https://hd.unsplash.com/photo-1416339306562-f3d12fefd36f",
"regular": "https://images.unsplash.com/photo-1416339306562-f3d12fefd36f?ixlib=rb-0.3.5&q=80&fm=jpg&crop=entropy&cs=tinysrgb&w=1080&fit=max&s=92f3e02f63678acc8416d044e189f515",
"small": "https://images.unsplash.com/photo-1416339306562-f3d12fefd36f?ixlib=rb-0.3.5&q=80&fm=jpg&crop=entropy&cs=tinysrgb&w=400&fit=max&s=263af33585f9d32af39d165b000845eb",
"thumb": "https://images.unsplash.com/photo-1416339306562-f3d12fefd36f?ixlib=rb-0.3.5&q=80&fm=jpg&crop=entropy&cs=tinysrgb&w=200&fit=max&s=8aae34cf35df31a592f0bef16e6342ef"
},
"links": {
"self": "https://api.unsplash.com/photos/eOLpJytrbsQ",
"html": "http://unsplash.com/photos/eOLpJytrbsQ",
"download": "http://unsplash.com/photos/eOLpJytrbsQ/download"
}
},
// more photos ...
]
}
【问题讨论】：
-
先查看有没有报错，再查看响应：
if let httpResponse = response as? HTTPURLResponse { ... }，再查看状态码 -
我更新了我的问题以显示完整的错误。它表明缺少总计，但如果我删除总计，错误将更改为“没有与键 CodingKeys 关联的值（字符串值：\“结果\”，intValue：nil）（\“结果\”）。”，基础错误：nil ))"
-
您可能遇到了错误，而不是您预期的响应。所以，检查服务器错误
-
在
guard let data行之后打印接收到的字符串：print(String(data: data, encoding: .utf8)!)。我敢肯定它揭示了 JSON 格式的错误。 -
@SpikeThea，那将是一个不同的问题 - 所以，应该是一个不同的问题。但就像我说的 - 也许不是很清楚 - 你遇到了服务器错误，并且 JSON 不是你期望解码的响应，因此你看到的解码错误