Swift可通过不一致的API进行解码

struct User: Codable {
    let id: Int
    let name: String
    let email: String

    enum CodingKeys: String, CodingKey {
        case id = "user_id"
        case name = "user_name"
        case email = "user_email"
    }
}

struct User: Codable {
    let id: Int
    let name: String
    let email: String?

    enum CodingKeys: String, CodingKey {
        case id = "user_id"
        case name = "user_name"
        case email = "user_email"
    }
}

let json = """
{
    "user_id": 1,
    "user_name": "John Doe"
}
""".data(using: .utf8)!

do {
    let user = try JSONDecoder().decode(User.self, from: json)
    print(user)
} catch {
    print("Failed to decode JSON: \(error)")
}

struct User: Codable {
    let id: Int
    let name: String
    let email: String?

    enum CodingKeys: String, CodingKey {
        case id = "user_id"
        case name = "user_name"
        case email = "user_email"
    }

    init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)
        id = try container.decode(Int.self, forKey: .id)
        name = try container.decode(String.self, forKey: .name)
        email = try container.decodeIfPresent(String.self, forKey: .email)
    }
}