如何在 Swift 中执行 GET 和 POST 请求？
How do I perform GET and POST requests in Swift?
我改编自 Ray Wenderlich 的 iOS 学徒教程第 4 部分。
此代码作为 GET 请求发送到我的 Strongloop API，具有简单的数据库模型，但是：
这行得通，但我不知道它为什么行得通，因为它没有调用我可以看到的实际发送请求的方法。
我看不出有什么办法可以将其变成 POST 请求。
我的问题是：如何执行 POST 请求？它是以完全不同的方式完成的吗？
如果您需要更多信息，请告诉我。
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
@IBAction func getFromDB() {
let url = urlWithSearchText("")
println("URL: '\(url)'")
if let jsonString = performGetRequestWithURL(url) {
println("Received JSON string '\(jsonString)'")
}
}
func urlWithSearchText(searchText: String) -> NSURL {
let escapedSearchText = searchText.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)!
let urlString = String(format: "http://localhost:3000/api/Tests", escapedSearchText)
let url = NSURL(string: urlString)
return url!
}
func performGetRequestWithURL(url: NSURL) -> String? {
var error: NSError?
if let resultString = String(contentsOfURL: url, encoding: NSUTF8StringEncoding, error: &error) {
return resultString
} else if let error = error {
println("Download Error: \(error)")
} else {
println("Unknown Download Error")
}
return nil
}
这是一张工作照片：
https://dl.dropboxusercontent.com/u/14464971/Images/Messages%20Image%281477993527%29.png
此方法调用 http 请求。
String(contentsOfURL: url, encoding: NSUTF8StringEncoding, error: &error)
因为Swift String没有这样的初始化签名
这个方法会写在项目的某处，如extension of String
会是这样的
extension String{
init(contentsOfURL: NSURL, encoding: NSUTF8StringEncoding, inout error: NSError){
// load data from url
self = //parse data to string
}
}
下面是两种POST方法。取决于你是想让它同步（其他一切都等到 post 方法完成）还是异步（POST 方法 运行s 在后台，其他方法 运行 并行） .
方法
// POST data to url
func postDataAsynchronous(url: String, bodyData: String, completionHandler: (responseString: String!, error: NSError!) -> ()) {
var URL: NSURL = NSURL(string: url)!
var request:NSMutableURLRequest = NSMutableURLRequest(URL:URL)
request.HTTPMethod = "POST";
request.HTTPBody = bodyData.dataUsingEncoding(NSUTF8StringEncoding);
NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue.mainQueue()){
response, data, error in
var output: String!
if data != nil {
output = NSString(data: data, encoding: NSUTF8StringEncoding) as! String
}
completionHandler(responseString: output, error: error)
}
}
// Obtain the data
func postDataSynchronous(url: String, bodyData: String, completionHandler: (responseString: String!, error: NSError!) -> ())
{
let URL: NSURL = NSURL(string: url)!
var request:NSMutableURLRequest = NSMutableURLRequest(URL:URL)
request.HTTPMethod = "POST"
request.HTTPBody = bodyData.dataUsingEncoding(NSUTF8StringEncoding);
request.addValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
var response: NSURLResponse?
var error: NSError?
// Send data
let data = NSURLConnection.sendSynchronousRequest(request, returningResponse: &response, error: &error)
var output: String! // Default to nil
if data != nil{
output = NSString(data: data!, encoding: NSUTF8StringEncoding) as! String
}
completionHandler(responseString: output, error: error)
}
使用它们
然后您可以像这样调用（使用）它们：
postDataSynchronous(url, bodyData: bodyData) {
responseString, error in
if error != nil {
println("Error during post: \(error)")
return
}
else{
//Success
println(responseString)
userType = responseString // Set usertype based on server response
}
}
SWIFT 2.0
func postData(url: String, params: Dictionary<String, String>, completionHandler: (data: NSData?, response: NSURLResponse?, error: NSError?) -> ()) {
// Indicate download
UIApplication.sharedApplication().networkActivityIndicatorVisible = true
let url = NSURL(string: url)!
// print("URL: \(url)")
let request = NSMutableURLRequest(URL: url)
let session = NSURLSession.sharedSession()
request.HTTPMethod = "POST"
request.addValue("application/json", forHTTPHeaderField: "Content-Type")
request.addValue("application/json", forHTTPHeaderField: "Accept")
// Verify downloading data is allowed
do {
request.HTTPBody = try NSJSONSerialization.dataWithJSONObject(params, options: [])
} catch let error as NSError {
print("Error in request post: \(error)")
request.HTTPBody = nil
} catch {
print("Catch all error: \(error)")
}
// Post the data
let task = session.dataTaskWithRequest(request) { data, response, error in
completionHandler(data: data, response: response, error: error)
// Stop download indication
UIApplication.sharedApplication().networkActivityIndicatorVisible = false // Stop download indication
}
task.resume()
}
String(contentsOfUrl:encoding:error) 初始化程序在后台发出 GET 请求，returns 内容作为具有指定编码的字符串。
发出请求的一种方法是创建一个 NSURLConnection 并使用 NSMutablrURLRequest 设置 HTTP 方法 post。使用 NSMutableURLRequest，您可以创建一个 NSURLConnection 并使用委托立即启动它，或者您可以调用 NSURLConnection.sendSynchronousRequest 或 NSURLConnection.sendAsynchronousRequest 来发送请求。
Swift 3 岁及以上
GET
func getRequest() {
// request url
let url = URL(string: "https://jsonplaceholder.typicode.com/todos/1")! // change the url
// create URLSession with default configuration
let session = URLSession.shared
// create dataTask using the session object to send data to the server
let task = session.dataTask(with: url) { data, response, error in
if let error = error {
print("GET Request Error: \(error.localizedDescription)")
return
}
// ensure there is valid response code returned from this HTTP response
guard let httpResponse = response as? HTTPURLResponse,
(200...299).contains(httpResponse.statusCode) else {
print("Invalid Response received from the server")
return
}
// ensure there is data returned
guard let responseData = data else {
print("nil Data received from the server")
return
}
do {
// serialise the data object into Dictionary [String : Any]
if let jsonResponse = try JSONSerialization.jsonObject(with: responseData, options: .mutableContainers) as? [String: Any] {
print(jsonResponse)
} else {
print("data maybe corrupted or in wrong format")
throw URLError(.badServerResponse)
}
} catch let error {
print("JSON Parsing Error: \(error.localizedDescription)")
}
}
// resume the task
task.resume()
}
POST
func postRequest() {
// declare the parameter as a dictionary that contains string as key and value combination. considering inputs are valid
let parameters: [String: Any] = ["name": "abc", "password": "password@123"]
// create the url with URL
let url = URL(string: "http://myServerName.com/api")! //change the url
// create the session object
let session = URLSession.shared
// now create the URLRequest object using the url object
var request = URLRequest(url: url)
request.httpMethod = "POST" //set http method as POST
// add headers for the request
request.addValue("application/json", forHTTPHeaderField: "Content-Type") // change as per server requirements
request.addValue("application/json", forHTTPHeaderField: "Accept")
do {
// convert parameters to Data and assign dictionary to httpBody of request
request.httpBody = try JSONSerialization.data(withJSONObject: parameters, options: .prettyPrinted)
} catch let error {
print(error.localizedDescription)
return
}
// create dataTask using the session object to send data to the server
let task = session.dataTask(with: request) { data, response, error in
if let error = error {
print("Post Request Error: \(error.localizedDescription)")
return
}
// ensure there is valid response code returned from this HTTP response
guard let httpResponse = response as? HTTPURLResponse,
(200...299).contains(httpResponse.statusCode)
else {
print("Invalid Response received from the server")
return
}
// ensure there is data returned
guard let responseData = data else {
print("nil Data received from the server")
return
}
do {
// create json object from data or use JSONDecoder to convert to Model stuct
if let jsonResponse = try JSONSerialization.jsonObject(with: responseData, options: .mutableContainers) as? [String: Any] {
print(jsonResponse)
// handle json response
} else {
print("data maybe corrupted or in wrong format")
throw URLError(.badServerResponse)
}
} catch let error {
print(error.localizedDescription)
}
}
task.resume()
}
guard let url = URL(string: "https://jsonplaceholder.typicode.com/users") else { return }
let session = URLSession.shared
session.dataTask(with: url) { (data, response, error) in
if let response = response {
print(response)
}
if let data = data {
print(data)
do {
let json = try JSONSerialization.jsonObject(with: data, options: [])
print(json)
} catch {
print(error)
}
}
}.resume()
}
这是一个get方法。
let parameters = ["username": "@Bipin_kumar", "tweet": "HelloWorld"]
guard let url = URL(string: "https://jsonplaceholder.typicode.com/posts") else { return }
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.addValue("application/json", forHTTPHeaderField: "Content-Type")
guard let httpBody = try? JSONSerialization.data(withJSONObject: parameters, options: []) else { return }
request.httpBody = httpBody
let session = URLSession.shared
session.dataTask(with: request) { (data, response, error) in
if let response = response {
print(response)
}
if let data = data {
do {
let json = try JSONSerialization.jsonObject(with: data, options: [])
print(json)
} catch {
print(error)
}
}
}.resume()
这是一个post方法。
GET 请求
func getRequest(with url: URL, callback: @escaping (Any?) -> Swift.Void) -> Void {
let defaultConfigObject = URLSessionConfiguration.default
defaultConfigObject.timeoutIntervalForRequest = 30.0
defaultConfigObject.timeoutIntervalForResource = 60.0
let session = URLSession.init(configuration: defaultConfigObject, delegate: nil, delegateQueue: nil)
var urlRequest = URLRequest(url: url as URL)
urlRequest.addValue("application/json", forHTTPHeaderField: "Content-Type")
urlRequest.httpMethod = "GET"
session.dataTask(with: urlRequest, completionHandler: { (data, response, error) in
guard let httpResponse: HTTPURLResponse = response as? HTTPURLResponse
else {
print("Error: did not receive data")
return
}
var response : (Any)? = nil
if httpResponse.statusCode == 200 {
print(httpResponse)
guard let responseData = data else {
print("Error: did not receive data")
return
}
do {
let responseData = try JSONSerialization.jsonObject(with: responseData, options: [JSONSerialization.ReadingOptions.allowFragments])
response = responseData
callback(response)
}
catch _ as NSError {
let responseString = NSString(data: data!, encoding: String.Encoding.utf8.rawValue)
callback(responseString)
return
}
}
else {
print(httpResponse)
guard error == nil else {
print("error calling GET on /todos/1")
print(error ?? "error")
callback(response!)
return
}
}
}).resume()
}
POST 请求
//MARK: post request
func postRequest(with url:URL, postBody:String, callback: @escaping (Any?) -> Void) -> Void {
let defaultConfigObject = URLSessionConfiguration.default
defaultConfigObject.timeoutIntervalForRequest = 30.0
defaultConfigObject.timeoutIntervalForResource = 60.0
let session = URLSession.init(configuration: defaultConfigObject, delegate: nil, delegateQueue: nil)
let params: String! = postBody
var urlRequest = URLRequest(url: url as URL)
urlRequest.httpMethod = "POST"
let data = params.data(using: String.Encoding(rawValue: String.Encoding.utf8.rawValue))
urlRequest.httpBody = data
session.dataTask(with: urlRequest, completionHandler: { (data, urlResponse, error) in
guard let httpResponse:HTTPURLResponse = urlResponse as? HTTPURLResponse
else{
print("did not get any data")
return
}
var response : (Any)? = nil
if httpResponse.statusCode == 200 {
guard let responseData = data else {
print("Error: did not receive data")
return
}
do {
guard let responseData = try JSONSerialization.jsonObject(with: responseData, options: []) as? [String: AnyObject] else {
print("error trying to convert data to JSON")
return
}
response = responseData
callback(response)
} catch _ as NSError {
let responseString = NSString(data: data!, encoding: String.Encoding.utf8.rawValue)
callback(responseString)
return
}
}
else {
guard error == nil else {
print("error calling GET on /todos/1")
print(error ?? "error")
callback(nil)
return
}
}
}).resume()
}
始终尝试检查 HTTPURLResponse 代码
我改编自 Ray Wenderlich 的 iOS 学徒教程第 4 部分。
此代码作为 GET 请求发送到我的 Strongloop API，具有简单的数据库模型，但是：
这行得通，但我不知道它为什么行得通，因为它没有调用我可以看到的实际发送请求的方法。
我看不出有什么办法可以将其变成 POST 请求。
我的问题是：如何执行 POST 请求？它是以完全不同的方式完成的吗？
如果您需要更多信息，请告诉我。
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
@IBAction func getFromDB() {
let url = urlWithSearchText("")
println("URL: '\(url)'")
if let jsonString = performGetRequestWithURL(url) {
println("Received JSON string '\(jsonString)'")
}
}
func urlWithSearchText(searchText: String) -> NSURL {
let escapedSearchText = searchText.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)!
let urlString = String(format: "http://localhost:3000/api/Tests", escapedSearchText)
let url = NSURL(string: urlString)
return url!
}
func performGetRequestWithURL(url: NSURL) -> String? {
var error: NSError?
if let resultString = String(contentsOfURL: url, encoding: NSUTF8StringEncoding, error: &error) {
return resultString
} else if let error = error {
println("Download Error: \(error)")
} else {
println("Unknown Download Error")
}
return nil
}
这是一张工作照片：
https://dl.dropboxusercontent.com/u/14464971/Images/Messages%20Image%281477993527%29.png
此方法调用 http 请求。
String(contentsOfURL: url, encoding: NSUTF8StringEncoding, error: &error)
因为Swift String没有这样的初始化签名
这个方法会写在项目的某处，如extension of String
会是这样的
extension String{
init(contentsOfURL: NSURL, encoding: NSUTF8StringEncoding, inout error: NSError){
// load data from url
self = //parse data to string
}
}
下面是两种POST方法。取决于你是想让它同步（其他一切都等到 post 方法完成）还是异步（POST 方法 运行s 在后台，其他方法 运行 并行） .
方法
// POST data to url
func postDataAsynchronous(url: String, bodyData: String, completionHandler: (responseString: String!, error: NSError!) -> ()) {
var URL: NSURL = NSURL(string: url)!
var request:NSMutableURLRequest = NSMutableURLRequest(URL:URL)
request.HTTPMethod = "POST";
request.HTTPBody = bodyData.dataUsingEncoding(NSUTF8StringEncoding);
NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue.mainQueue()){
response, data, error in
var output: String!
if data != nil {
output = NSString(data: data, encoding: NSUTF8StringEncoding) as! String
}
completionHandler(responseString: output, error: error)
}
}
// Obtain the data
func postDataSynchronous(url: String, bodyData: String, completionHandler: (responseString: String!, error: NSError!) -> ())
{
let URL: NSURL = NSURL(string: url)!
var request:NSMutableURLRequest = NSMutableURLRequest(URL:URL)
request.HTTPMethod = "POST"
request.HTTPBody = bodyData.dataUsingEncoding(NSUTF8StringEncoding);
request.addValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
var response: NSURLResponse?
var error: NSError?
// Send data
let data = NSURLConnection.sendSynchronousRequest(request, returningResponse: &response, error: &error)
var output: String! // Default to nil
if data != nil{
output = NSString(data: data!, encoding: NSUTF8StringEncoding) as! String
}
completionHandler(responseString: output, error: error)
}
使用它们
然后您可以像这样调用（使用）它们：
postDataSynchronous(url, bodyData: bodyData) {
responseString, error in
if error != nil {
println("Error during post: \(error)")
return
}
else{
//Success
println(responseString)
userType = responseString // Set usertype based on server response
}
}
SWIFT 2.0
func postData(url: String, params: Dictionary<String, String>, completionHandler: (data: NSData?, response: NSURLResponse?, error: NSError?) -> ()) {
// Indicate download
UIApplication.sharedApplication().networkActivityIndicatorVisible = true
let url = NSURL(string: url)!
// print("URL: \(url)")
let request = NSMutableURLRequest(URL: url)
let session = NSURLSession.sharedSession()
request.HTTPMethod = "POST"
request.addValue("application/json", forHTTPHeaderField: "Content-Type")
request.addValue("application/json", forHTTPHeaderField: "Accept")
// Verify downloading data is allowed
do {
request.HTTPBody = try NSJSONSerialization.dataWithJSONObject(params, options: [])
} catch let error as NSError {
print("Error in request post: \(error)")
request.HTTPBody = nil
} catch {
print("Catch all error: \(error)")
}
// Post the data
let task = session.dataTaskWithRequest(request) { data, response, error in
completionHandler(data: data, response: response, error: error)
// Stop download indication
UIApplication.sharedApplication().networkActivityIndicatorVisible = false // Stop download indication
}
task.resume()
}
String(contentsOfUrl:encoding:error) 初始化程序在后台发出 GET 请求，returns 内容作为具有指定编码的字符串。
发出请求的一种方法是创建一个 NSURLConnection 并使用 NSMutablrURLRequest 设置 HTTP 方法 post。使用 NSMutableURLRequest，您可以创建一个 NSURLConnection 并使用委托立即启动它，或者您可以调用 NSURLConnection.sendSynchronousRequest 或 NSURLConnection.sendAsynchronousRequest 来发送请求。
Swift 3 岁及以上
GET
func getRequest() {
// request url
let url = URL(string: "https://jsonplaceholder.typicode.com/todos/1")! // change the url
// create URLSession with default configuration
let session = URLSession.shared
// create dataTask using the session object to send data to the server
let task = session.dataTask(with: url) { data, response, error in
if let error = error {
print("GET Request Error: \(error.localizedDescription)")
return
}
// ensure there is valid response code returned from this HTTP response
guard let httpResponse = response as? HTTPURLResponse,
(200...299).contains(httpResponse.statusCode) else {
print("Invalid Response received from the server")
return
}
// ensure there is data returned
guard let responseData = data else {
print("nil Data received from the server")
return
}
do {
// serialise the data object into Dictionary [String : Any]
if let jsonResponse = try JSONSerialization.jsonObject(with: responseData, options: .mutableContainers) as? [String: Any] {
print(jsonResponse)
} else {
print("data maybe corrupted or in wrong format")
throw URLError(.badServerResponse)
}
} catch let error {
print("JSON Parsing Error: \(error.localizedDescription)")
}
}
// resume the task
task.resume()
}
POST
func postRequest() {
// declare the parameter as a dictionary that contains string as key and value combination. considering inputs are valid
let parameters: [String: Any] = ["name": "abc", "password": "password@123"]
// create the url with URL
let url = URL(string: "http://myServerName.com/api")! //change the url
// create the session object
let session = URLSession.shared
// now create the URLRequest object using the url object
var request = URLRequest(url: url)
request.httpMethod = "POST" //set http method as POST
// add headers for the request
request.addValue("application/json", forHTTPHeaderField: "Content-Type") // change as per server requirements
request.addValue("application/json", forHTTPHeaderField: "Accept")
do {
// convert parameters to Data and assign dictionary to httpBody of request
request.httpBody = try JSONSerialization.data(withJSONObject: parameters, options: .prettyPrinted)
} catch let error {
print(error.localizedDescription)
return
}
// create dataTask using the session object to send data to the server
let task = session.dataTask(with: request) { data, response, error in
if let error = error {
print("Post Request Error: \(error.localizedDescription)")
return
}
// ensure there is valid response code returned from this HTTP response
guard let httpResponse = response as? HTTPURLResponse,
(200...299).contains(httpResponse.statusCode)
else {
print("Invalid Response received from the server")
return
}
// ensure there is data returned
guard let responseData = data else {
print("nil Data received from the server")
return
}
do {
// create json object from data or use JSONDecoder to convert to Model stuct
if let jsonResponse = try JSONSerialization.jsonObject(with: responseData, options: .mutableContainers) as? [String: Any] {
print(jsonResponse)
// handle json response
} else {
print("data maybe corrupted or in wrong format")
throw URLError(.badServerResponse)
}
} catch let error {
print(error.localizedDescription)
}
}
task.resume()
}
guard let url = URL(string: "https://jsonplaceholder.typicode.com/users") else { return }
let session = URLSession.shared
session.dataTask(with: url) { (data, response, error) in
if let response = response {
print(response)
}
if let data = data {
print(data)
do {
let json = try JSONSerialization.jsonObject(with: data, options: [])
print(json)
} catch {
print(error)
}
}
}.resume()
}
这是一个get方法。
let parameters = ["username": "@Bipin_kumar", "tweet": "HelloWorld"]
guard let url = URL(string: "https://jsonplaceholder.typicode.com/posts") else { return }
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.addValue("application/json", forHTTPHeaderField: "Content-Type")
guard let httpBody = try? JSONSerialization.data(withJSONObject: parameters, options: []) else { return }
request.httpBody = httpBody
let session = URLSession.shared
session.dataTask(with: request) { (data, response, error) in
if let response = response {
print(response)
}
if let data = data {
do {
let json = try JSONSerialization.jsonObject(with: data, options: [])
print(json)
} catch {
print(error)
}
}
}.resume()
这是一个post方法。
GET 请求
func getRequest(with url: URL, callback: @escaping (Any?) -> Swift.Void) -> Void {
let defaultConfigObject = URLSessionConfiguration.default
defaultConfigObject.timeoutIntervalForRequest = 30.0
defaultConfigObject.timeoutIntervalForResource = 60.0
let session = URLSession.init(configuration: defaultConfigObject, delegate: nil, delegateQueue: nil)
var urlRequest = URLRequest(url: url as URL)
urlRequest.addValue("application/json", forHTTPHeaderField: "Content-Type")
urlRequest.httpMethod = "GET"
session.dataTask(with: urlRequest, completionHandler: { (data, response, error) in
guard let httpResponse: HTTPURLResponse = response as? HTTPURLResponse
else {
print("Error: did not receive data")
return
}
var response : (Any)? = nil
if httpResponse.statusCode == 200 {
print(httpResponse)
guard let responseData = data else {
print("Error: did not receive data")
return
}
do {
let responseData = try JSONSerialization.jsonObject(with: responseData, options: [JSONSerialization.ReadingOptions.allowFragments])
response = responseData
callback(response)
}
catch _ as NSError {
let responseString = NSString(data: data!, encoding: String.Encoding.utf8.rawValue)
callback(responseString)
return
}
}
else {
print(httpResponse)
guard error == nil else {
print("error calling GET on /todos/1")
print(error ?? "error")
callback(response!)
return
}
}
}).resume()
}
POST 请求
//MARK: post request
func postRequest(with url:URL, postBody:String, callback: @escaping (Any?) -> Void) -> Void {
let defaultConfigObject = URLSessionConfiguration.default
defaultConfigObject.timeoutIntervalForRequest = 30.0
defaultConfigObject.timeoutIntervalForResource = 60.0
let session = URLSession.init(configuration: defaultConfigObject, delegate: nil, delegateQueue: nil)
let params: String! = postBody
var urlRequest = URLRequest(url: url as URL)
urlRequest.httpMethod = "POST"
let data = params.data(using: String.Encoding(rawValue: String.Encoding.utf8.rawValue))
urlRequest.httpBody = data
session.dataTask(with: urlRequest, completionHandler: { (data, urlResponse, error) in
guard let httpResponse:HTTPURLResponse = urlResponse as? HTTPURLResponse
else{
print("did not get any data")
return
}
var response : (Any)? = nil
if httpResponse.statusCode == 200 {
guard let responseData = data else {
print("Error: did not receive data")
return
}
do {
guard let responseData = try JSONSerialization.jsonObject(with: responseData, options: []) as? [String: AnyObject] else {
print("error trying to convert data to JSON")
return
}
response = responseData
callback(response)
} catch _ as NSError {
let responseString = NSString(data: data!, encoding: String.Encoding.utf8.rawValue)
callback(responseString)
return
}
}
else {
guard error == nil else {
print("error calling GET on /todos/1")
print(error ?? "error")
callback(nil)
return
}
}
}).resume()
}
始终尝试检查 HTTPURLResponse 代码