Json Swift：访问1220个面顶点并从AR面保存顶点

我正在尝试获取1220顶点数据并将其保存到iPhone文件中。我遇到的问题是无法获取捕获的数据并将其正确写入JSON结构

我有：

struct CaptureData {
    var vertices: [SIMD3<Float>]


      var verticesFormatted : String {
            let v = "<" + vertices.map{ "\($0.x):\($0.y):\($0.z)" }.joined(separator: "~") + "~t:\(String(Double(Date().timeIntervalSince1970)))>"
            return "\(v)"
        }

    var jsonDict:Dictionary<String, Any> = [
           "facetracking_data" : "1",
           "info" : [
               "frame" : "0",
               "timestamp" : 12345,
               "vertices" : [
                   "x" : "0.1",
                   "y" : "0.2",
                   "z" : "0.3"
               ]
           ]
       ]

    var jsonData : Data {
        let data = try! JSONSerialization.data(withJSONObject: jsonDict, options: .prettyPrinted)
        return data
    }

}

---

我无法获取try数据。写入（to:fileURL，原子性：false，编码：.utf8）此操作将正常工作，因为它返回错误（'data'没有'write'的成员）我不太确定如何获取捕获的数据并将其写入我定义的JSON结构…

有人能帮我吗？有人能帮我吗？有人吗？？？请帮我吗？？？请帮我吗？？？请帮我吗？有人能帮我吗？有人吗？？？请帮我吗有人帮忙吗？？？请帮忙

@IBAction func saveButtonTapped(_ sender: UIButton) {
     guard let data = getFrameData() else {return}

                      let jsonDataString = String(decoding: data.jsonData, as: UTF8.self)
                      let file = "\(UUID().uuidString).txt"
                      let dir = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
                      let fileURL = dir.appendingPathComponent(file)
                      do {

                          try data.write(to: fileURL, atomically: false, encoding: .utf8)
                        print(data)
                      }
                      catch {
                          print("Error: \(error)")
                      }
    }