Swift 结构可编码但无法编码

Swift Struct is Codable but can't encode

struct KOTextPrompt: Codable {
    let prompt: String
    let response: String
}

我有一个非常简单的 Codable 结构。我一直在尝试使用 Alamofire 将其作为参数传递并发生崩溃

2019-07-31 14:52:00.894242-0700 Kirby[8336:1685359] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Invalid type in JSON write (__SwiftValue)'

我尝试打印下面的代码并得到 "false"。我做错了什么?

let gg = KOTextPrompt(prompt: "testprompt", response: "testresponse")
        print(JSONSerialization.isValidJSONObject(gg))

这里的问题是作为 KOTextPromptit 实例的 gg 不是有效的 JSON 对象。您需要对结构进行编码:

struct KOTextPrompt: Codable {
    let prompt, response: String
}

let gg = KOTextPrompt(prompt: "testprompt", response: "testresponse")
do {
    let data = try JSONEncoder().encode(gg)
    print("json string:", String(data: data, encoding: .utf8) ?? "")
    let jsonObject = try JSONSerialization.jsonObject(with: data)
    print("json object:", jsonObject)
} catch { print(error) }

这将打印

json string: {"response":"testresponse","prompt":"testprompt"}

json object: { prompt = testprompt; response = testresponse; }