Question

JSON：

{
   "words": "1"
}

有时是键words或word

解析此JSON时失败，并显示以下错误

错误：

keyNotFound（CodingKeys（stringValue：“ paragraph”，intValue：nil），Swift.DecodingError.Context（codingPath：[]，debugDescription：“没有与键CodingKeys（stringValue：\” paragraph \“，intValue：nil相关联的值））（\“ paragraph \”）。“，underlyingError：nil））。段落是

@objcMembers class EmphasisModel: NSObject ,Codable{
    var words:String?
}
enum CodingKeys: String, CodingKey {
    case word,words
}

required init(from decoder: Decoder) throws {
    let container = try decoder.container(keyedBy: CodingKeys.self)
    self.words = try container.decode(String?.self, forKey: .words)

    if self.words != nil {
            self.words = try container.decode(String?.self, forKey: .word)
    }
}

Answer 1

您应在decodeIfPresent期间使用decoding。 if statement是错误的。它应该检查是否等于nil而不是non-nil。

class EmphasisModel: Decodable {

    var words: String?

    enum CodingKeys: String, CodingKey {
        case word, words
    }

    required init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)

        self.words = try container.decodeIfPresent(String.self, forKey: .words)

        if self.words == nil {
            self.words = try container.decodeIfPresent(String.self, forKey: .word)
        }
    }
}

用法

let data = """
          { "words": "1" }
         """.data(using: .utf8)!
do {
    let ad = try JSONDecoder().decode(EmphasisModel.self, from: data)
    print(ad?.words)
} catch {
    print(error)
}

NSObject Decodable相同的值

1 个答案: