使用 Alamofire 为参数发送“Null”值

Posted 2023-03-04

【中文标题】使用 Alamofire 为参数发送“Null”值

【英文标题】：Sending a `Null` value for parameter with Alamofire

【发布时间】：2016-10-13 20:13:50

【问题描述】：

我已经更新到 Swift3 和最新的 Alamofire '~> 4.0' 当我尝试设置我的参数时，我现在得到<null> 而不是null 用于我没有设置的设置。这与我的后端冲突。

有没有办法发送null？

当我将值设置为 nil 时，它不包含在 put 中，字典会将其删除。但我需要发回所有值。

我的代码

func saveOfficeHours(days: [OfficeHours]) 
  guard let URL = LocationInfo.shared.url else 
    assertionFailure("location URL is nil")
    return
    

  let formatter = DateFormatter()
  formatter.dateFormat = "HH:mm:ss"

  func formatTime(time: Date?) -> Any 
      guard let time = time else  return NSNull() 
      return formatter.string(from: time)
  

  var parameters: [String: Any] = [:]
  for week in days 
    parameters["\(week.day)_hours_start"] = formatTime(time: week.hoursStart)
    parameters["\(week.day)_hours_stop"] =  formatTime(time: week.hoursEnd)
    parameters["\(week.day)_lunch_hours_start"] =  formatTime(time: week.lunchStart)
    parameters["\(week.day)_lunch_hours_stop"] =  formatTime(time: week.lunchEnd)
    parameters["\(week.day)_break_hours_start"] =  formatTime(time: week.breakStart)
    parameters["\(week.day)_break_hours_stop"] =  formatTime(time: week.breakEnd)
  

  Alamofire.request(URL, method: .put, parameters: parameters, encoding: URLEncoding.httpBody, headers: API.workstationTokenAuthHeaders()).validate().responseJSON 
    response in
    switch response.result 
    case .success:
        print("Success setting office hours")
    case .failure(let error):
        print("Failure setting office hours: \n \n -------==========-------- \n \n\(error)\n \n -------==========-------- \n")
    
  

提前感谢您的帮助。

【参考方案1】：

与其依靠 NSNull 通过 Alamofire 和通过 HTTP 发送的带有您的参数的数据之间的各种抽象来正确映射，我会执行以下操作：

func formatTime(time: Date?) -> String? 
  guard let time = time else  return nil 
  return formatter.string(from: time)


var parameters: [String: Any] = [:]
  for week in days 
    if let hoursStart = formatTime(time: week.hoursStart)  parameters["\(week.day)_hours_start"] = hoursStart  
    if let hoursEnd = formatTime(time: week.hoursEnd)  parameters["\(week.day)_hours_stop"] = hoursEnd  
    if let lunchStart = formatTime(time: week.lunchStart)  parameters["\(week.day)_lunch_hours_start"] =  lunchStart  
    if let lunchStop = formatTime(time: week.lunchEnd)  parameters["\(week.day)_lunch_hours_stop"] = lunchStop  
    if let breakStart = formatTime(time: week.breakStart)  parameters["\(week.day)_break_hours_start"] = breakHoursStart  
    if let breakEnd = formatTime(time: week.breakEnd)  parameters["\(week.day)_break_hours_stop"] = breakEnd   
  

顺便说一句，您的问题应该说明您在哪里看到 <null> 而不是 null？在 Cocoa 中的一些日志记录调用中，还是在您的服务器端？尽管如此，更安全（并且可以说是 Swiftier，因为在上面的示例中 formatTime 具有有意义的返回类型）选项将高于 IMO。