Swift4DateDecodable.swift

import Foundation

let myDate = """
{
    "name": "jr",
    "data": "sjkdhfjsdhf",
    "updated":"2017-10-10 10:38:25.722 UTC"
}
"""

enum DateError: String, Error {
    case invalidDate
}

struct MyDate: Decodable {
    let updated: Date?
    let name: String?
    let data: String?
}

enum DateError: String, Error {
    case invalidDate
}

struct Object: Decodable {
    let updated: Date?
    let name: String?
    let data: String?
}

let data = Data(myDate.utf8)

let formatter = DateFormatter()
formatter.dateFormat = "yyyy-MM-dd HH:mm:ss.SSSXXXXX"

let decoder = JSONDecoder()
decoder.dateDecodingStrategy = .formatted(formatter)

let dateResult = try! decoder.decode(Object.self, from: data)

print(dateResult)