在Swift中向用户显示网络错误消息
问题是如何使代码可重用，特别是网络方法中的错误检查和completionhandler中的条件，这样就不会有重复的代码了 我创建了一个方法，该方法使用URLSession发出网络请求，并使用statuscode作为参数调用完成处理程序。在完成处理中，我创建了一个条件，根据状态码显示错误消息或执行序列。所有这些代码都可以工作，但我想使其可重用，这样我就不会有重复的代码 联网方法：在Swift中向用户显示网络错误消息,swift,networking,error-handling,completionhandler,urlsession,Swift,Networking,Error Handling,Completionhandler,Urlsession,问题是如何使代码可重用，特别是网络方法中的错误检查和completionhandler中的条件，这样就不会有重复的代码了 我创建了一个方法，该方法使用URLSession发出网络请求，并使用statuscode作为参数调用完成处理程序。在完成处理中，我创建了一个条件，根据状态码显示错误消息或执行序列。所有这些代码都可以工作，但我想使其可重用，这样我就不会有重复的代码 联网方法： func saveMessage(data: String, day: String, completion: @es
func saveMessage(data: String, day: String, completion: @escaping (Int)->()) {
let url = URL(string: "\(Constants.baseURL)/daily_mindset/today_message")
guard let requestUrl = url else { fatalError() }
var request = URLRequest(url: requestUrl)
request.httpMethod = "POST"
// Set HTTP Request Header
request.setValue("application/json", forHTTPHeaderField: "Accept")
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
let jsonData = encodeJSON(with: data, day: day)
request.httpBody = jsonData
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
if error != nil {
completion(700)
return
}
guard let response = response as? HTTPURLResponse else {
completion(701)
return
}
guard (200...299).contains(response.statusCode) else {
completion(response.statusCode)
return
}
guard let mime = response.mimeType, mime == "application/json" else {
completion(702)
return
}
guard let data = data else {
completion(703)
return
}
do {
let todoItemModel = try JSONDecoder().decode(MessageData.self, from: data)
Constants.currentMindsetId = todoItemModel._id!
print("Response data:\n \(todoItemModel)")
} catch let jsonErr{
print(jsonErr)
}
completion(response.statusCode)
}
task.resume()
}
messageManager.saveMessage(data: textView.text, day: day, completion: {(statusCode: Int) -> Void in
if (200...299).contains(statusCode) {
DispatchQueue.main.async {
self.performSegue(withIdentifier: "ToDailyMindsetScreen", sender: sender)
}
} else if (400...499).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Please make sure you filled in the all the required fields."
}
} else if (500...599).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, couldn't reach our server."
}
} else if (700...).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, something went wrong. Try again later."
}
}
})
if error != nil {
completion(700)
return
}
guard let response = response as? HTTPURLResponse else {
completion(701)
return
}
guard (200...299).contains(response.statusCode) else {
completion(response.statusCode)
return
}
guard let mime = response.mimeType, mime == "application/json" else {
completion(702)
return
}
guard let data = data else {
completion(703)
return
}
if (200...299).contains(statusCode) {
DispatchQueue.main.async {
self.performSegue(withIdentifier: "ToDailyMindsetScreen", sender: sender)
}
} else if (400...499).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Please make sure you filled in the all the required fields."
}
} else if (500...599).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, couldn't reach our server."
}
} else if (700...).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, something went wrong. Try again later."
}
}
func saveMessage(data: String, day: String, completion: @escaping (Int)->()) {
let url = URL(string: "\(Constants.baseURL)/daily_mindset/today_message")
guard let requestUrl = url else { fatalError() }
var request = URLRequest(url: requestUrl)
request.httpMethod = "POST"
// Set HTTP Request Header
request.setValue("application/json", forHTTPHeaderField: "Accept")
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
let jsonData = encodeJSON(with: data, day: day)
request.httpBody = jsonData
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
if error != nil {
completion(700)
return
}
guard let response = response as? HTTPURLResponse else {
completion(701)
return
}
guard (200...299).contains(response.statusCode) else {
completion(response.statusCode)
return
}
guard let mime = response.mimeType, mime == "application/json" else {
completion(702)
return
}
guard let data = data else {
completion(703)
return
}
do {
let todoItemModel = try JSONDecoder().decode(MessageData.self, from: data)
Constants.currentMindsetId = todoItemModel._id!
print("Response data:\n \(todoItemModel)")
} catch let jsonErr{
print(jsonErr)
}
completion(response.statusCode)
}
task.resume()
}
messageManager.saveMessage(data: textView.text, day: day, completion: {(statusCode: Int) -> Void in
if (200...299).contains(statusCode) {
DispatchQueue.main.async {
self.performSegue(withIdentifier: "ToDailyMindsetScreen", sender: sender)
}
} else if (400...499).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Please make sure you filled in the all the required fields."
}
} else if (500...599).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, couldn't reach our server."
}
} else if (700...).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, something went wrong. Try again later."
}
}
})
if error != nil {
completion(700)
return
}
guard let response = response as? HTTPURLResponse else {
completion(701)
return
}
guard (200...299).contains(response.statusCode) else {
completion(response.statusCode)
return
}
guard let mime = response.mimeType, mime == "application/json" else {
completion(702)
return
}
guard let data = data else {
completion(703)
return
}
if (200...299).contains(statusCode) {
DispatchQueue.main.async {
self.performSegue(withIdentifier: "ToDailyMindsetScreen", sender: sender)
}
} else if (400...499).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Please make sure you filled in the all the required fields."
}
} else if (500...599).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, couldn't reach our server."
}
} else if (700...).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, something went wrong. Try again later."
}
}
func saveMessage(data: String, day: String, completion: @escaping (Int)->()) {
let url = URL(string: "\(Constants.baseURL)/daily_mindset/today_message")
guard let requestUrl = url else { fatalError() }
var request = URLRequest(url: requestUrl)
request.httpMethod = "POST"
// Set HTTP Request Header
request.setValue("application/json", forHTTPHeaderField: "Accept")
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
let jsonData = encodeJSON(with: data, day: day)
request.httpBody = jsonData
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
if error != nil {
completion(700)
return
}
guard let response = response as? HTTPURLResponse else {
completion(701)
return
}
guard (200...299).contains(response.statusCode) else {
completion(response.statusCode)
return
}
guard let mime = response.mimeType, mime == "application/json" else {
completion(702)
return
}
guard let data = data else {
completion(703)
return
}
do {
let todoItemModel = try JSONDecoder().decode(MessageData.self, from: data)
Constants.currentMindsetId = todoItemModel._id!
print("Response data:\n \(todoItemModel)")
} catch let jsonErr{
print(jsonErr)
}
completion(response.statusCode)
}
task.resume()
}
messageManager.saveMessage(data: textView.text, day: day, completion: {(statusCode: Int) -> Void in
if (200...299).contains(statusCode) {
DispatchQueue.main.async {
self.performSegue(withIdentifier: "ToDailyMindsetScreen", sender: sender)
}
} else if (400...499).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Please make sure you filled in the all the required fields."
}
} else if (500...599).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, couldn't reach our server."
}
} else if (700...).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, something went wrong. Try again later."
}
}
})
if error != nil {
completion(700)
return
}
guard let response = response as? HTTPURLResponse else {
completion(701)
return
}
guard (200...299).contains(response.statusCode) else {
completion(response.statusCode)
return
}
guard let mime = response.mimeType, mime == "application/json" else {
completion(702)
return
}
guard let data = data else {
completion(703)
return
}
if (200...299).contains(statusCode) {
DispatchQueue.main.async {
self.performSegue(withIdentifier: "ToDailyMindsetScreen", sender: sender)
}
} else if (400...499).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Please make sure you filled in the all the required fields."
}
} else if (500...599).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, couldn't reach our server."
}
} else if (700...).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, something went wrong. Try again later."
}
}
func saveMessage(data: String, day: String, completion: @escaping (Int)->()) {
let url = URL(string: "\(Constants.baseURL)/daily_mindset/today_message")
guard let requestUrl = url else { fatalError() }
var request = URLRequest(url: requestUrl)
request.httpMethod = "POST"
// Set HTTP Request Header
request.setValue("application/json", forHTTPHeaderField: "Accept")
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
let jsonData = encodeJSON(with: data, day: day)
request.httpBody = jsonData
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
if error != nil {
completion(700)
return
}
guard let response = response as? HTTPURLResponse else {
completion(701)
return
}
guard (200...299).contains(response.statusCode) else {
completion(response.statusCode)
return
}
guard let mime = response.mimeType, mime == "application/json" else {
completion(702)
return
}
guard let data = data else {
completion(703)
return
}
do {
let todoItemModel = try JSONDecoder().decode(MessageData.self, from: data)
Constants.currentMindsetId = todoItemModel._id!
print("Response data:\n \(todoItemModel)")
} catch let jsonErr{
print(jsonErr)
}
completion(response.statusCode)
}
task.resume()
}
messageManager.saveMessage(data: textView.text, day: day, completion: {(statusCode: Int) -> Void in
if (200...299).contains(statusCode) {
DispatchQueue.main.async {
self.performSegue(withIdentifier: "ToDailyMindsetScreen", sender: sender)
}
} else if (400...499).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Please make sure you filled in the all the required fields."
}
} else if (500...599).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, couldn't reach our server."
}
} else if (700...).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, something went wrong. Try again later."
}
}
})
if error != nil {
completion(700)
return
}
guard let response = response as? HTTPURLResponse else {
completion(701)
return
}
guard (200...299).contains(response.statusCode) else {
completion(response.statusCode)
return
}
guard let mime = response.mimeType, mime == "application/json" else {
completion(702)
return
}
guard let data = data else {
completion(703)
return
}
if (200...299).contains(statusCode) {
DispatchQueue.main.async {
self.performSegue(withIdentifier: "ToDailyMindsetScreen", sender: sender)
}
} else if (400...499).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Please make sure you filled in the all the required fields."
}
} else if (500...599).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, couldn't reach our server."
}
} else if (700...).contains(statusCode) {
DispatchQueue.main.async {
self.errorLabel.text = "Sorry, something went wrong. Try again later."
}
}
如果错误消息特定于ViewController，则可以创建一个函数，该函数根据以下状态代码返回消息：
private func getErrorMessageFor(statusCode: Int) -> String? {
if (200...299).contains(statusCode) {
//If no error message is returned assume that the request was a success
return nil
} else if (400...499).contains(statusCode) {
return "Please make sure you filled in the all the required fields."
} else if (500...599).contains(statusCode) {
return "Sorry, couldn't reach our server."
} else if (700...).contains(statusCode) {
return "Sorry, something went wrong. Try again later."
} else {
return "Message for other errors?"
}
}
class BaseViewController: UIViewController {
func getErrorMessageFor(statusCode: Int) -> String? {
//base implementation here
}
}
class OtherViewController: BaseViewController {
override func getErrorMessageFor(statusCode: Int) -> String? {
//create a new error message only for statusCode 404
if statusCode == 404 {
return "The requested resource was not found on the server. Please contact the support team"
} else {
return super.getErrorMessageFor(statusCode: statusCode)
}
}
}
请记住，随着应用程序的增长，您可能希望创建一个APIClient来为您处理网络和错误处理。看一看，它对用户非常友好也许你应该把它发布在