将未知对象解码为Swift中的原始形式

Question

我有Rawjson类，它曾经存储和操作未知结构的对象，无法解码。

public indirect enum RawJSON: Codable, Hashable {
    case number(Double)
    case string(String)
    case bool(Bool)
    case dictionary([String: RawJSON])
    case array([RawJSON])
    case `nil`

    static let double = number

    public init(from decoder: Decoder) throws {
        let singleValueContainer = try decoder.singleValueContainer()
        if let value = try? singleValueContainer.decode(Bool.self) {
            self = .bool(value)
            return
        } else if let value = try? singleValueContainer.decode(String.self) {
            self = .string(value)
            return
        } else if let value = try? singleValueContainer.decode(Double.self) {
            self = .number(value)
            return
        } else if let value = try? singleValueContainer.decode([String: RawJSON].self) {
            self = .dictionary(value)
            return
        } else if let value = try? singleValueContainer.decode([RawJSON].self) {
            self = .array(value)
            return
        } else if singleValueContainer.decodeNil() {
            self = .nil
            return
        }
        throw DecodingError
            .dataCorrupted(
                DecodingError
                    .Context(codingPath: decoder.codingPath, debugDescription: "Could not find reasonable type to map to JSONValue")
            )
    }
    
    public func encode(to encoder: Encoder) throws {
        var container = encoder.singleValueContainer()
        switch self {
        case let .number(value): try container.encode(value)
        case let .bool(value): try container.encode(value)
        case let .string(value): try container.encode(value)
        case let .array(value): try container.encode(value)
        case let .dictionary(value): try container.encode(value)
        case .nil: try container.encodeNil()
        }
    }
}

public extension RawJSON {
    func dictionary(with value: RawJSON?, forKey key: String) -> RawJSON? {
        guard case var .dictionary(content) = self else { return nil }
        content[key] = value
        return .dictionary(content)
    }
}
public indirect enum RawJSON: Codable, Hashable {
    case number(Double)
    case string(String)
    case bool(Bool)
    case dictionary([String: RawJSON])
    case array([RawJSON])
    case `nil`

    static let double = number

    public init(from decoder: Decoder) throws {
        let singleValueContainer = try decoder.singleValueContainer()
        if let value = try? singleValueContainer.decode(Bool.self) {
            self = .bool(value)
            return
        } else if let value = try? singleValueContainer.decode(String.self) {
            self = .string(value)
            return
        } else if let value = try? singleValueContainer.decode(Double.self) {
            self = .number(value)
            return
        } else if let value = try? singleValueContainer.decode([String: RawJSON].self) {
            self = .dictionary(value)
            return
        } else if let value = try? singleValueContainer.decode([RawJSON].self) {
            self = .array(value)
            return
        } else if singleValueContainer.decodeNil() {
            self = .nil
            return
        }
        throw DecodingError
            .dataCorrupted(
                DecodingError
                    .Context(codingPath: decoder.codingPath, debugDescription: "Could not find reasonable type to map to JSONValue")
            )
    }
    
    public func encode(to encoder: Encoder) throws {
        var container = encoder.singleValueContainer()
        switch self {
        case let .number(value): try container.encode(value)
        case let .bool(value): try container.encode(value)
        case let .string(value): try container.encode(value)
        case let .array(value): try container.encode(value)
        case let .dictionary(value): try container.encode(value)
        case .nil: try container.encodeNil()
        }
    }
}

public extension RawJSON {
    func dictionary(with value: RawJSON?, forKey key: String) -> RawJSON? {
        guard case var .dictionary(content) = self else { return nil }
        content[key] = value
        return .dictionary(content)
    }
}

我想要字符串的原始形式。

如何将其解码为原始字符串？

let RAWJSONArray = [RawJSON.string("A"),RawJSON.string("B"),RawJSON.string("C")]
        let arrayString : [String] = []
        for item in RAWJSONArray {
            arrayString.append(item) <-- error No exact matches in call to instance method 'append'  
        }

我使用客户端从StreamChat API使用此类来客户聊天，他们存储了额外的数据并将其转换为RAWJSON类型对象并将其发送到API。

Answer 1

这做您需要的吗？

var arrayString : [String] = []
let encoder = JSONEncoder()

for item in RAWJSONArray {
    if let data = try? encoder.encode(item),
    let str = String(data: data, encoding: .utf8) {             
       arrayString.append(str)
    }
}

也许您真的只想要琴弦？

for case let .string(str) in RAWJSONArray {
    arrayString.append(str)
}