Swift 可解码 - 解码具有 Base64 编码字符串的 json

Question

我正在尝试解码编码base64的JSON响应。

示例JSON：

{ "contract": "JVBERi0xLjQKJeLjz9MKNSAwIG9iago8PC9UeXBlL1hPYmplY3QvQ29sb3JTcGFjZS9EZXZpY2V", "isSuccess": true }

• 如何将base64解码为字符串？

我的代码＆amp;模型：

struct ruleModel: Codable {
    let contract: String?
    let isSuccess: Bool?
 }


let decoder = JSONDecoder()
let response = try decoder.decode(ruleModel.self, from: result! as! Data)
print(response)

解码错误：

dataCorrupted(Swift.DecodingError.Context(codingPath: [], debugDescription: "The given data was not valid JSON.", underlyingError: Optional(Error Domain=NSCocoaErrorDomain Code=3840 "Invalid value around line 1, column 0." UserInfo={NSDebugDescription=Invalid value around line 1, column 0., NSJSONSerializationErrorIndex=0})))