问题
I read The Programming Language Swift by Apple in iBooks, but cannot figure out how to make an http request (something like CURL) in Swift. Do I need to import Obj-C classes or do I just need to import default libraries? Or is it not possible to make an HTTP request based on native swift code?
回答1:
You can use URL, URLRequest and URLSession or NSURLConnection as you'd normally do in Objective-C. Note that for iOS 7.0 and later, URLSession is preferred.
Using URLSession
Initialize a URL object and a URLSessionDataTask from URLSession. Then run the task with resume().
let url = URL(string: "http://www.stackoverflow.com")!
let task = URLSession.shared.dataTask(with: url) {(data, response, error) in
guard let data = data else { return }
print(String(data: data, encoding: .utf8)!)
}
task.resume()
Using NSURLConnection
First, initialize a URL and a URLRequest:
let url = URL(string: "http://www.stackoverflow.com")!
var request = URLRequest(url: url)
request.httpMethod = "POST"
Then, you can load the request asynchronously with:
NSURLConnection.sendAsynchronousRequest(request, queue: OperationQueue.main) {(response, data, error) in
guard let data = data else { return }
print(String(data: data, encoding: .utf8)!)
}
Or you can initialize an NSURLConnection:
let connection = NSURLConnection(request: request, delegate:nil, startImmediately: true)
Just make sure to set your delegate to something other than nil and use the delegate methods to work with the response and data received.
For more detail, check the documentation for the NSURLConnectionDataDelegate protocol
Testing on an Xcode playground
If you want to try this code on a Xcode playground, add import PlaygroundSupport to your playground, as well as the following call:
PlaygroundPage.current.needsIndefiniteExecution = true
This will allow you to use asynchronous code in playgrounds.
回答2:
Check Below Codes :
1. SynchonousRequest
Swift 1.2
let urlPath: String = "YOUR_URL_HERE"
var url: NSURL = NSURL(string: urlPath)!
var request1: NSURLRequest = NSURLRequest(URL: url)
var response: AutoreleasingUnsafeMutablePointer<NSURLResponse?>=nil
var dataVal: NSData = NSURLConnection.sendSynchronousRequest(request1, returningResponse: response, error:nil)!
var err: NSError
println(response)
var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(dataVal, options: NSJSONReadingOptions.MutableContainers, error: &err) as? NSDictionary
println("Synchronous\(jsonResult)")
Swift 2.0 +
let urlPath: String = "YOUR_URL_HERE"
let url: NSURL = NSURL(string: urlPath)!
let request1: NSURLRequest = NSURLRequest(URL: url)
let response: AutoreleasingUnsafeMutablePointer<NSURLResponse?>=nil
do{
let dataVal = try NSURLConnection.sendSynchronousRequest(request1, returningResponse: response)
print(response)
do {
if let jsonResult = try NSJSONSerialization.JSONObjectWithData(dataVal, options: []) as? NSDictionary {
print("Synchronous\(jsonResult)")
}
} catch let error as NSError {
print(error.localizedDescription)
}
}catch let error as NSError
{
print(error.localizedDescription)
}
2. AsynchonousRequest
Swift 1.2
let urlPath: String = "YOUR_URL_HERE"
var url: NSURL = NSURL(string: urlPath)!
var request1: NSURLRequest = NSURLRequest(URL: url)
let queue:NSOperationQueue = NSOperationQueue()
NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse!, data: NSData!, error: NSError!) -> Void in
var err: NSError
var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as NSDictionary
println("Asynchronous\(jsonResult)")
})
Swift 2.0 +
let urlPath: String = "YOUR_URL_HERE"
let url: NSURL = NSURL(string: urlPath)!
let request1: NSURLRequest = NSURLRequest(URL: url)
let queue:NSOperationQueue = NSOperationQueue()
NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse?, data: NSData?, error: NSError?) -> Void in
do {
if let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: []) as? NSDictionary {
print("ASynchronous\(jsonResult)")
}
} catch let error as NSError {
print(error.localizedDescription)
}
})
3. As usual URL connection
Swift 1.2
var dataVal = NSMutableData()
let urlPath: String = "YOUR URL HERE"
var url: NSURL = NSURL(string: urlPath)!
var request: NSURLRequest = NSURLRequest(URL: url)
var connection: NSURLConnection = NSURLConnection(request: request, delegate: self, startImmediately: true)!
connection.start()
Then
func connection(connection: NSURLConnection!, didReceiveData data: NSData!){
self.dataVal?.appendData(data)
}
func connectionDidFinishLoading(connection: NSURLConnection!)
{
var error: NSErrorPointer=nil
var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(dataVal!, options: NSJSONReadingOptions.MutableContainers, error: error) as NSDictionary
println(jsonResult)
}
Swift 2.0 +
var dataVal = NSMutableData()
let urlPath: String = "YOUR URL HERE"
var url: NSURL = NSURL(string: urlPath)!
var request: NSURLRequest = NSURLRequest(URL: url)
var connection: NSURLConnection = NSURLConnection(request: request, delegate: self, startImmediately: true)!
connection.start()
Then
func connection(connection: NSURLConnection!, didReceiveData data: NSData!){
dataVal.appendData(data)
}
func connectionDidFinishLoading(connection: NSURLConnection!)
{
do {
if let jsonResult = try NSJSONSerialization.JSONObjectWithData(dataVal, options: []) as? NSDictionary {
print(jsonResult)
}
} catch let error as NSError {
print(error.localizedDescription)
}
}
4. Asynchonous POST Request
Swift 1.2
let urlPath: String = "YOUR URL HERE"
var url: NSURL = NSURL(string: urlPath)!
var request1: NSMutableURLRequest = NSMutableURLRequest(URL: url)
request1.HTTPMethod = "POST"
var stringPost="deviceToken=123456" // Key and Value
let data = stringPost.dataUsingEncoding(NSUTF8StringEncoding)
request1.timeoutInterval = 60
request1.HTTPBody=data
request1.HTTPShouldHandleCookies=false
let queue:NSOperationQueue = NSOperationQueue()
NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse!, data: NSData!, error: NSError!) -> Void in
var err: NSError
var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as NSDictionary
println("AsSynchronous\(jsonResult)")
})
Swift 2.0 +
let urlPath: String = "YOUR URL HERE"
let url: NSURL = NSURL(string: urlPath)!
let request1: NSMutableURLRequest = NSMutableURLRequest(URL: url)
request1.HTTPMethod = "POST"
let stringPost="deviceToken=123456" // Key and Value
let data = stringPost.dataUsingEncoding(NSUTF8StringEncoding)
request1.timeoutInterval = 60
request1.HTTPBody=data
request1.HTTPShouldHandleCookies=false
let queue:NSOperationQueue = NSOperationQueue()
NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse?, data: NSData?, error: NSError?) -> Void in
do {
if let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: []) as? NSDictionary {
print("ASynchronous\(jsonResult)")
}
} catch let error as NSError {
print(error.localizedDescription)
}
})
5. Asynchonous GET Request
Swift 1.2
let urlPath: String = "YOUR URL HERE"
var url: NSURL = NSURL(string: urlPath)!
var request1: NSMutableURLRequest = NSMutableURLRequest(URL: url)
request1.HTTPMethod = "GET"
request1.timeoutInterval = 60
let queue:NSOperationQueue = NSOperationQueue()
NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse!, data: NSData!, error: NSError!) -> Void in
var err: NSError
var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as NSDictionary
println("AsSynchronous\(jsonResult)")
})
Swift 2.0 +
let urlPath: String = "YOUR URL HERE"
let url: NSURL = NSURL(string: urlPath)!
let request1: NSMutableURLRequest = NSMutableURLRequest(URL: url)
request1.HTTPMethod = "GET"
let queue:NSOperationQueue = NSOperationQueue()
NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse?, data: NSData?, error: NSError?) -> Void in
do {
if let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: []) as? NSDictionary {
print("ASynchronous\(jsonResult)")
}
} catch let error as NSError {
print(error.localizedDescription)
}
})
6. Image(File) Upload
Swift 2.0 +
let mainURL = "YOUR_URL_HERE"
let url = NSURL(string: mainURL)
let request = NSMutableURLRequest(URL: url!)
let boundary = "78876565564454554547676"
request.addValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")
request.HTTPMethod = "POST" // POST OR PUT What you want
let session = NSURLSession(configuration:NSURLSessionConfiguration.defaultSessionConfiguration(), delegate: nil, delegateQueue: nil)
let imageData = UIImageJPEGRepresentation(UIImage(named: "Test.jpeg")!, 1)
var body = NSMutableData()
body.appendData("--\(boundary)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
// Append your parameters
body.appendData("Content-Disposition: form-data; name=\"name\"\r\n\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData("PREMKUMAR\r\n".dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)!)
body.appendData("--\(boundary)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData("Content-Disposition: form-data; name=\"description\"\r\n\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData("IOS_DEVELOPER\r\n".dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)!)
body.appendData("--\(boundary)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
// Append your Image/File Data
var imageNameval = "HELLO.jpg"
body.appendData("--\(boundary)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData("Content-Disposition: form-data; name=\"profile_photo\"; filename=\"\(imageNameval)\"\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData("Content-Type: image/jpeg\r\n\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData(imageData!)
body.appendData("\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData("--\(boundary)--\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
request.HTTPBody = body
let dataTask = session.dataTaskWithRequest(request) { (data, response, error) -> Void in
if error != nil {
//handle error
}
else {
let outputString : NSString = NSString(data:data!, encoding:NSUTF8StringEncoding)!
print("Response:\(outputString)")
}
}
dataTask.resume()
回答3:
Another option is the Alamofire lib that offers Chainable Request / Response methods.
https://github.com/Alamofire/Alamofire
Making a Request
import Alamofire
Alamofire.request(.GET, "http://httpbin.org/get")
Response Handling
Alamofire.request(.GET, "http://httpbin.org/get", parameters: ["foo": "bar"])
.response { request, response, data, error in
print(request)
print(response)
print(error)
}
回答4:
Swift 3 and Swift 4: Data Request using URLSession API
//create the url with NSURL
let url = URL(string: "https://jsonplaceholder.typicode.com/todos/1")! //change the url
//create the session object
let session = URLSession.shared
//now create the URLRequest object using the url object
let request = URLRequest(url: url)
//create dataTask using the session object to send data to the server
let task = session.dataTask(with: request as URLRequest, completionHandler: { data, response, error in
guard error == nil else {
return
}
guard let data = data else {
return
}
do {
//create json object from data
if let json = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as? [String: Any] {
print(json)
}
} catch let error {
print(error.localizedDescription)
}
})
task.resume()
Swift 4, Decodable and Result enum
//APPError enum which shows all possible errors
enum APPError: Error {
case networkError(Error)
case dataNotFound
case jsonParsingError(Error)
case invalidStatusCode(Int)
}
//Result enum to show success or failure
enum Result<T> {
case success(T)
case failure(APPError)
}
//dataRequest which sends request to given URL and convert to Decodable Object
func dataRequest<T: Decodable>(with url: String, objectType: T.Type, completion: @escaping (Result<T>) -> Void) {
//create the url with NSURL
let dataURL = URL(string: url)! //change the url
//create the session object
let session = URLSession.shared
//now create the URLRequest object using the url object
let request = URLRequest(url: dataURL, cachePolicy: .useProtocolCachePolicy, timeoutInterval: 60)
//create dataTask using the session object to send data to the server
let task = session.dataTask(with: request, completionHandler: { data, response, error in
guard error == nil else {
completion(Result.failure(AppError.networkError(error!)))
return
}
guard let data = data else {
completion(Result.failure(APPError.dataNotFound))
return
}
do {
//create decodable object from data
let decodedObject = try JSONDecoder().decode(objectType.self, from: data)
completion(Result.success(decodedObject))
} catch let error {
completion(Result.failure(APPError.jsonParsingError(error as! DecodingError)))
}
})
task.resume()
}
example:
//if we want to fetch todo from placeholder API, then we define the ToDo struct and call dataRequest and pass "https://jsonplaceholder.typicode.com/todos/1" string url.
struct ToDo: Decodable {
let id: Int
let userId: Int
let title: String
let completed: Bool
}
dataRequest(with: "https://jsonplaceholder.typicode.com/todos/1", objectType: ToDo.self) { (result: Result) in
switch result {
case .success(let object):
print(object)
case .failure(let error):
print(error)
}
}
//this prints the result:
ToDo(id: 1, userId: 1, title: "delectus aut autem", completed: false)
回答5:
Basic Swift 3 Solution
let url = URL(string: "http://www.stackoverflow.com")
let task = URLSession.shared.dataTask(with: url! as URL) { data, response, error in
guard let data = data, error == nil else { return }
print(NSString(data: data, encoding: String.Encoding.utf8.rawValue))
}
task.resume()
回答6:
I am using this guy's wrapper with good results so far https://github.com/daltoniam/swiftHTTP. No big leaky abstractions so far
Example
do {
let opt = try HTTP.GET("https://google.com")
opt.start { response in
if let err = response.error {
print("error: \(err.localizedDescription)")
return //also notify app of failure as needed
}
print("opt finished: \(response.description)")
//print("data is: \(response.data)") access the response of the data with response.data
}
} catch let error {
print("got an error creating the request: \(error)")
}
回答7:
Details
- Xcode 9.2, Swift 4
- Xcode 10.2.1 (10E1001), Swift 5
Info.plist
NSAppTransportSecurity
Add to the info plist:
<key>NSAppTransportSecurity</key>
<dict>
<key>NSAllowsArbitraryLoads</key>
<true/>
</dict>
Alamofire Sample
Alamofire
import Alamofire
class AlamofireDataManager {
fileprivate let queue: DispatchQueue
init(queue: DispatchQueue) { self.queue = queue }
private func createError(message: String, code: Int) -> Error {
return NSError(domain: "dataManager", code: code, userInfo: ["message": message ])
}
private func make(session: URLSession = URLSession.shared, request: URLRequest, closure: ((Result<[String: Any]>) -> Void)?) {
Alamofire.request(request).responseJSON { response in
let complete: (Result<[String: Any]>) ->() = { result in DispatchQueue.main.async { closure?(result) } }
switch response.result {
case .success(let value): complete(.success(value as! [String: Any]))
case .failure(let error): complete(.failure(error))
}
}
}
func searchRequest(term: String, closure: ((Result<[String: Any]>) -> Void)?) {
guard let url = URL(string: "https://itunes.apple.com/search?term=\(term.replacingOccurrences(of: " ", with: "+"))") else { return }
let request = URLRequest(url: url)
make(request: request) { response in closure?(response) }
}
}
Usage of Alamofire sample
private lazy var alamofireDataManager = AlamofireDataManager(queue: DispatchQueue(label: "DataManager.queue", qos: .utility))
//.........
alamofireDataManager.searchRequest(term: "jack johnson") { result in
print(result.value ?? "no data")
print(result.error ?? "no error")
}
URLSession Sample
import Foundation
class DataManager {
fileprivate let queue: DispatchQueue
init(queue: DispatchQueue) { self.queue = queue }
private func createError(message: String, code: Int) -> Error {
return NSError(domain: "dataManager", code: code, userInfo: ["message": message ])
}
private func make(session: URLSession = URLSession.shared, request: URLRequest, closure: ((_ json: [String: Any]?, _ error: Error?)->Void)?) {
let task = session.dataTask(with: request) { [weak self] data, response, error in
self?.queue.async {
let complete: (_ json: [String: Any]?, _ error: Error?) ->() = { json, error in DispatchQueue.main.async { closure?(json, error) } }
guard let self = self, error == nil else { complete(nil, error); return }
guard let data = data else { complete(nil, self.createError(message: "No data", code: 999)); return }
do {
if let json = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as? [String: Any] {
complete(json, nil)
}
} catch let error { complete(nil, error); return }
}
}
task.resume()
}
func searchRequest(term: String, closure: ((_ json: [String: Any]?, _ error: Error?)->Void)?) {
let url = URL(string: "https://itunes.apple.com/search?term=\(term.replacingOccurrences(of: " ", with: "+"))")
let request = URLRequest(url: url!)
make(request: request) { json, error in closure?(json, error) }
}
}
Usage of URLSession sample
private lazy var dataManager = DataManager(queue: DispatchQueue(label: "DataManager.queue", qos: .utility))
// .......
dataManager.searchRequest(term: "jack johnson") { json, error in
print(error ?? "nil")
print(json ?? "nil")
print("Update views")
}
Results
回答8:
I have done HTTP Request Both methods GET & POST with JSON Parsing this way:
on viewDidLoad():
override func viewDidLoad() {
super.viewDidLoad()
makeGetRequest()
makePostRequest()
}
func makePostRequest(){
let urlPath: String = "http://www.swiftdeveloperblog.com/http-post-example-script/"
var url: NSURL = NSURL(string: urlPath)!
var request: NSMutableURLRequest = NSMutableURLRequest(URL: url)
request.HTTPMethod = "POST"
var stringPost="firstName=James&lastName=Bond" // Key and Value
let data = stringPost.dataUsingEncoding(NSUTF8StringEncoding)
request.timeoutInterval = 60
request.HTTPBody=data
request.HTTPShouldHandleCookies=false
let queue:NSOperationQueue = NSOperationQueue()
NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue(), completionHandler:{ (response:NSURLResponse!, data: NSData!, error: NSError!) -> Void in
var error: AutoreleasingUnsafeMutablePointer<NSError?> = nil
let jsonResult: NSDictionary! = NSJSONSerialization.JSONObjectWithData(data, options:NSJSONReadingOptions.MutableContainers, error: error) as? NSDictionary
if (jsonResult != nil) {
// Success
println(jsonResult)
let message = jsonResult["Message"] as! NSString
println(message)
}else {
// Failed
println("Failed")
}
})
}
func makeGetRequest(){
var url : String = "http://api.androidhive.info/contacts/"
var request : NSMutableURLRequest = NSMutableURLRequest()
request.URL = NSURL(string: url)
request.HTTPMethod = "GET"
request.timeoutInterval = 60
NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue(), completionHandler:{ (response:NSURLResponse!, data: NSData!, error: NSError!) -> Void in
var error: AutoreleasingUnsafeMutablePointer<NSError?> = nil
let jsonResult: NSDictionary! = NSJSONSerialization.JSONObjectWithData(data, options:NSJSONReadingOptions.MutableContainers, error: error) as? NSDictionary
if (jsonResult != nil) {
// Success
println(jsonResult)
let dataArray = jsonResult["contacts"] as! NSArray;
for item in dataArray { // loop through data items
let obj = item as! NSDictionary
for (key, value) in obj {
println("Key: \(key) - Value: \(value)")
let phone = obj["phone"] as! NSDictionary;
let mobile = phone["mobile"] as! NSString
println(mobile)
let home = phone["home"] as! NSString
println(home)
let office = phone["office"] as! NSString
println(office)
}
}
} else {
// Failed
println("Failed")
}
})
}
Done
回答9:
I am calling the json on login button click
@IBAction func loginClicked(sender : AnyObject) {
var request = NSMutableURLRequest(URL: NSURL(string: kLoginURL)) // Here, kLogin contains the Login API.
var session = NSURLSession.sharedSession()
request.HTTPMethod = "POST"
var err: NSError?
request.HTTPBody = NSJSONSerialization.dataWithJSONObject(self.criteriaDic(), options: nil, error: &err) // This Line fills the web service with required parameters.
request.addValue("application/json", forHTTPHeaderField: "Content-Type")
request.addValue("application/json", forHTTPHeaderField: "Accept")
var task = session.dataTaskWithRequest(request, completionHandler: {data, response, error -> Void in
var strData = NSString(data: data, encoding: NSUTF8StringEncoding)
var err1: NSError?
var json2 = NSJSONSerialization.JSONObjectWithData(strData.dataUsingEncoding(NSUTF8StringEncoding), options: .MutableLeaves, error:&err1 ) as NSDictionary
println("json2 :\(json2)")
if(err) {
println(err!.localizedDescription)
}
else {
var success = json2["success"] as? Int
println("Success: \(success)")
}
})
task.resume()
}
Here, I have made a seperate dictionary for the parameters.
var params = ["format":"json", "MobileType":"IOS","MIN":"f8d16d98ad12acdbbe1de647414495ec","UserName":emailTxtField.text,"PWD":passwordTxtField.text,"SigninVia":"SH"]as NSDictionary
return params
}
// You can add your own sets of parameter here.
回答10:
You can use Just, a python-requests style HTTP library.
Some example of sending HTTP request with Just:
// synchronous GET request with URL query a=1
let r = Just.get("https://httpbin.org/get", params:["a":1])
// asynchronous POST request with form value and file uploads
Just.post(
"http://justiceleauge.org/member/register",
data: ["username": "barryallen", "password":"ReverseF1ashSucks"],
files: ["profile_photo": .URL(fileURLWithPath:"flash.jpeg", nil)]
) { (r)
if (r.ok) { /* success! */ }
}
In both cases, the result of a request r can be accessed in ways similar to python-request:
r.ok // is the response successful?
r.statusCode // status code of response
r.content // response body as NSData?
r.text // response body as text?
r.json // response body parsed by NSJSONSerielization
You can find more examples in this playground
Using this library in synchronous mode in a playground is the closest thing to cURL one can get in Swift.
回答11:
In Swift 4.1 and Xcode 9.4.1.
JSON POST approach example. To check internet connection add Reachability.h & .m files from https://developer.apple.com/library/archive/samplecode/Reachability/Introduction/Intro.html#//apple_ref/doc/uid/DTS40007324-Intro-DontLinkElementID_2
func yourFunctionName {
//Check internet connection
let networkReachability = Reachability.forInternetConnection()
let networkStatus:Int = (networkReachability?.currentReachabilityStatus())!.rawValue
print(networkStatus)
if networkStatus == NotReachable.rawValue {
let msg = SharedClass.sharedInstance.noNetMsg//Message
//Call alert from shared class
SharedClass.sharedInstance.alert(view: self, title: "", message: msg)
} else {
//Call spinner from shared class
SharedClass.sharedInstance.activityIndicator(view: self.view)//Play spinner
let parameters = "Your parameters here"
var request = URLRequest(url: URL(string: url)!)
request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
request.httpMethod = "POST"
print("URL : \(request)")
request.httpBody = parameters.data(using: .utf8)
let task = URLSession.shared.dataTask(with: request) { data, response, error in guard let data = data, error == nil else { // check for fundamental networking error
//Stop spinner
SharedClass.sharedInstance.stopActivityIndicator() //Stop spinner
//Print error in alert
SharedClass.sharedInstance.alert(view: self, title: "", message: "\(String(describing: error!.localizedDescription))")
return
}
SharedClass.sharedInstance.stopActivityIndicator() //Stop spinner
if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 { // check for http errors
print("statusCode should be 200, but is \(httpStatus.statusCode)")
print("response = \(String(describing: response))")
}
do {
let response = try JSONSerialization.jsonObject(with: data, options: []) as? [String: AnyObject]
print(response!)
//Your code here
} catch let error as NSError {
print(error)
}
}
task.resume()
}
}
If you have interest to use this function in SharedClass
//My shared class
import UIKit
class SharedClass: NSObject {
static let sharedInstance = SharedClass()
func postRequestFunction(apiName: String , parameters: String, onCompletion: @escaping (_ success: Bool, _ error: Error?, _ result: [String: Any]?)->()) {
var URL = "your URL here/index.php/***?"
URL = URL.replacingOccurrences(of: "***", with: apiName)
var request = URLRequest(url: URL(string: URL)!)
request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
request.httpMethod = "POST"
print("shared URL : \(request)")
request.httpBody = parameters.data(using: .utf8)
var returnRes:[String:Any] = [:]
let task = URLSession.shared.dataTask(with: request) { data, response, error in
if let error = error {
onCompletion(false, error, nil)
} else {
guard let data = data else {
onCompletion(false, error, nil)
return
}
if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode == 200 {
do {
returnRes = try JSONSerialization.jsonObject(with: data, options: []) as! [String : Any]
onCompletion(true, nil, returnRes)
} catch let error as NSError {
onCompletion(false, error, nil)
}
} else {
onCompletion(false, error, nil)
}
}
}
task.resume()
}
private override init() {
}
And finally call this function like this....
SharedClass.sharedInstance.postRequestFunction(apiName: "Your API name", parameters: parameters) { (success, error, result) in
print(result!)
if success {
//Your code here
} else {
print(error?.localizedDescription ?? "")
}
}
回答12:
Using URLSession + Swift 5
Just adding to cezar's answer, if you want to make web request using Apple's URLSession class, there are multiple way to do the task
- Simple GET Request with URL
- Simple GET Request with URL and Parameters
- Simple GET Request with URL with Error Handlings
- Simple POST Request with URL, Parameters with Error Handlings
1. Simple GET Request with URL
func simpleGetUrlRequest()
{
let url = URL(string: "https://httpbin.org/get")!
let task = URLSession.shared.dataTask(with: url) {(data, response, error) in
guard let data = data else { return }
print("The response is : ",String(data: data, encoding: .utf8)!)
//print(NSString(data: data, encoding: String.Encoding.utf8.rawValue) as Any)
}
task.resume()
}
Note : Make sure You must add "NSAppTransportSecurity" key in pList for http requests
<key>NSAppTransportSecurity</key>
<dict>
<key>NSAllowsArbitraryLoads</key>
<true/>
</dict>
2. Simple GET Request with URL and Parameters
func simpleGetUrlWithParamRequest()
{
let url = URL(string: "https://www.google.com/search?q=peace")!
let task = URLSession.shared.dataTask(with: url) {(data, response, error) in
if error != nil || data == nil {
print("Client error!")
return
}
guard let response = response as? HTTPURLResponse, (200...299).contains(response.statusCode) else {
print("Server error!")
return
}
print("The Response is : ",response)
}
task.resume()
}
3. Simple GET Request with URL with Error Handlings
func simpleGetUrlRequestWithErrorHandling()
{
let session = URLSession.shared
let url = URL(string: "https://httpbin.org/get")!
let task = session.dataTask(with: url) { data, response, error in
if error != nil || data == nil {
print("Client error!")
return
}
guard let response = response as? HTTPURLResponse, (200...299).contains(response.statusCode) else {
print("Server error!")
return
}
guard let mime = response.mimeType, mime == "application/json" else {
print("Wrong MIME type!")
return
}
do {
let json = try JSONSerialization.jsonObject(with: data!, options: [])
print("The Response is : ",json)
} catch {
print("JSON error: \(error.localizedDescription)")
}
}
task.resume()
}
4. Simple POST Request with URL, Parameters with Error Handlings.
func simplePostRequestWithParamsAndErrorHandling(){
var session = URLSession.shared
let configuration = URLSessionConfiguration.default
configuration.timeoutIntervalForRequest = 30
configuration.timeoutIntervalForResource = 30
session = URLSession(configuration: configuration)
let url = URL(string: "https://httpbin.org/post")!
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
request.addValue("application/json", forHTTPHeaderField: "Accept")
let parameters = ["username": "foo", "password": "123456"]
do {
request.httpBody = try JSONSerialization.data(withJSONObject: parameters, options: .prettyPrinted)
} catch let error {
print(error.localizedDescription)
}
let task = session.dataTask(with: request as URLRequest, completionHandler: { data, response, error in
if error != nil || data == nil {
print("Client error!")
return
}
guard let response = response as? HTTPURLResponse, (200...299).contains(response.statusCode) else {
print("Oops!! there is server error!")
return
}
guard let mime = response.mimeType, mime == "application/json" else {
print("response is not json")
return
}
do {
let json = try JSONSerialization.jsonObject(with: data!, options: [])
print("The Response is : ",json)
} catch {
print("JSON error: \(error.localizedDescription)")
}
})
task.resume()
}
Your suggestions are appreciated!!
回答13:
A simple Swift 2.0 approach to making a HTTP GET request
The HTTP request is asynchronous so you need a way to get the returned value from the HTTP Request. This approach uses Notifiers and is spread over two classes.
The example is to check the username and password for an identifier token using the website http://www.example.com/handler.php?do=CheckUserJson&json= That is the file is called handler.php and has a switch statement on the do parameter to get a RESTful approach.
In the viewDidLoad we setup the NotifierObserver, set up the json and make the call to the getHTTPRequest function. It will return to the function checkedUsernameAndPassword with the returned parameter from the http request.
override func viewDidLoad() {
super.viewDidLoad()
// setup the Notification observer to catch the result of check username and password
NSNotificationCenter.defaultCenter().addObserver(self, selector: "checkedUsernameAndPassword:", name: CHECK_USERNAME_AND_PASSWORD, object: nil)
let username = GlobalVariables.USER_NAME
let password = GlobalVariables.PASSWORD
// check username and password
if let jsonString = Utility.checkUsernameAndPasswordJson(username, password:password){
print("json string returned = \(jsonString)")
let url = CHECKUSERJSON+jsonString
// CHECKUSERJSON = http://www.example.com/handler.php?do=CheckUserJson&json=
// jsonString = {\"username\":\"demo\",\"password\":\"demo\"}"
// the php script handles a json request and returns a string identifier
Utility.getHTTPRequest(url,notifierId: CHECK_USERNAME_AND_PASSWORD)
// the returned identifier is sent to the checkedUsernaeAndPassword function when it becomes availabel.
}
}
There are two static functions in Utility.swift first to encode the json and then to do the HTTP call.
static func checkUsernameAndPasswordJson(username: String, password: String) -> String?{
let para:NSMutableDictionary = NSMutableDictionary()
para.setValue("demo", forKey: "username")
para.setValue("demo", forKey: "password")
let jsonData: NSData
do{
jsonData = try NSJSONSerialization.dataWithJSONObject(para, options: NSJSONWritingOptions())
let jsonString = NSString(data: jsonData, encoding: NSUTF8StringEncoding) as! String
return jsonString
} catch _ {
print ("UH OOO")
return nil
}
}
and the Http request
static func getHTTPRequest (url:String , notifierId: String) -> Void{
let urlString = url
let config = NSURLSessionConfiguration.defaultSessionConfiguration()
let session = NSURLSession(configuration: config, delegate: nil, delegateQueue: nil)
let safeURL = urlString.stringByAddingPercentEncodingWithAllowedCharacters(NSCharacterSet.URLQueryAllowedCharacterSet())!
if let url = NSURL(string: safeURL){
let request = NSMutableURLRequest(URL: url)
request.HTTPMethod = "GET"
request.timeoutInterval = 60
let taskData = session.dataTaskWithRequest(request, completionHandler: {
(data:NSData?, response:NSURLResponse?, error:NSError?) -> Void in
if (data != nil) {
let result = NSString(data: data! , encoding: NSUTF8StringEncoding)
sendNotification (notifierId, message: String(result), num: 0)
}else{
sendNotification (notifierId, message: String(UTF8String: nil), num: -1) }
})
taskData.resume()
}else{
print("bad urlString = \(urlString)")
}
}
The sendNotification function completes the circle. Notice that in teh Observer there is a ":" at the end of the selector string. This allows the notification to carry a payload in userInfo. I give this a String and an Int.
static func sendNotification (key: String, message:String?, num: Int?){
NSNotificationCenter.defaultCenter().postNotificationName(
key,
object: nil,
userInfo: (["message": message!,
"num": "\(num!)"])
)
}
Note that using HTTP is oldFashioned, prefer HTTPS see How do I load an HTTP URL with App Transport Security enabled in iOS 9?
回答14:
var post:NSString = "api=myposts&userid=\(uid)&page_no=0&limit_no=10"
NSLog("PostData: %@",post);
var url1:NSURL = NSURL(string: url)!
var postData:NSData = post.dataUsingEncoding(NSASCIIStringEncoding)!
var postLength:NSString = String( postData.length )
var request:NSMutableURLRequest = NSMutableURLRequest(URL: url1)
request.HTTPMethod = "POST"
request.HTTPBody = postData
request.setValue(postLength, forHTTPHeaderField: "Content-Length")
request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
request.setValue("application/json", forHTTPHeaderField: "Accept")
var reponseError: NSError?
var response: NSURLResponse?
var urlData: NSData? = NSURLConnection.sendSynchronousRequest(request, returningResponse:&response, error:&reponseError)
if ( urlData != nil ) {
let res = response as NSHTTPURLResponse!;
NSLog("Response code: %ld", res.statusCode);
if (res.statusCode >= 200 && res.statusCode < 300)
{
var responseData:NSString = NSString(data:urlData!, encoding:NSUTF8StringEncoding)!
NSLog("Response ==> %@", responseData);
var error: NSError?
let jsonData:NSDictionary = NSJSONSerialization.JSONObjectWithData(urlData!, options:NSJSONReadingOptions.MutableContainers , error: &error) as NSDictionary
let success:NSInteger = jsonData.valueForKey("error") as NSInteger
//[jsonData[@"success"] integerValue];
NSLog("Success: %ld", success);
if(success == 0)
{
NSLog("Login SUCCESS");
self.dataArr = jsonData.valueForKey("data") as NSMutableArray
self.table.reloadData()
} else {
NSLog("Login failed1");
ZAActivityBar.showErrorWithStatus("error", forAction: "Action2")
}
} else {
NSLog("Login failed2");
ZAActivityBar.showErrorWithStatus("error", forAction: "Action2")
}
} else {
NSLog("Login failed3");
ZAActivityBar.showErrorWithStatus("error", forAction: "Action2")
}
it will help you surely
回答15:
//Here is an example that worked for me
//Swift function that post a request to a server with key values
func insertRecords()
{
let usrID = txtID.text
let checkin = lblInOut.text
let comment = txtComment.text
// The address of the web service
let urlString = "http://your_url/checkInOut_post.php"
// These are the keys that your are sending as part of the post request
let keyValues = "id=\(usrID)&inout=\(checkin)&comment=\(comment)"
// 1 - Create the session by getting the configuration and then
// creating the session
let config = NSURLSessionConfiguration.defaultSessionConfiguration()
let session = NSURLSession(configuration: config, delegate: nil, delegateQueue: nil)
// 2 - Create the URL Object
if let url = NSURL(string: urlString){
// 3 - Create the Request Object
var request = NSMutableURLRequest(URL: url)
request.HTTPMethod = "POST"
// set the key values
request.HTTPBody = keyValues.dataUsingEncoding(NSUTF8StringEncoding);
// 4 - execute the request
let taskData = session.dataTaskWithRequest(request, completionHandler: {
(data:NSData!, response:NSURLResponse!, error:NSError!) -> Void in
println("\(data)")
// 5 - Do something with the Data back
if (data != nil) {
// we got some data back
println("\(data)")
let result = NSString(data: data , encoding: NSUTF8StringEncoding)
println("\(result)")
if result == "OK" {
let a = UIAlertView(title: "OK", message: "Attendece has been recorded", delegate: nil, cancelButtonTitle: "OK")
println("\(result)")
dispatch_async(dispatch_get_main_queue()) {
a.show()
}
} else {
// display error and do something else
}
} else
{ // we got an error
println("Error getting stores :\(error.localizedDescription)")
}
})
taskData.resume()
}
}
PHP Code to get the key values
$empID = $_POST['id'];
$inOut = $_POST['inout'];
$comment = $_POST['comment'];
回答16:
Here's a very simple Swift 4 example in a playground:
import UIKit
// run asynchronously in a playground
import PlaygroundSupport
PlaygroundPage.current.needsIndefiniteExecution = true
// create a url
let url = URL(string: "http://www.stackoverflow.com")
// create a data task
let task = URLSession.shared.dataTask(with: url!) { (data, response, error) in
if error != nil {
print("there's a problem")
}
print(String(data: data!, encoding: String.Encoding.utf8) ?? "")
}
//running the task w/ resume
task.resume()
回答17:
For XCUITest to stop the test finishing before the async request completes use this (maybe reduce the 100 timeout):
func test_api() {
let url = URL(string: "https://jsonplaceholder.typicode.com/posts/42")!
let exp = expectation(description: "Waiting for data")
let task = URLSession.shared.dataTask(with: url) {(data, response, error) in
guard let data = data else { return }
print(String(data: data, encoding: .utf8)!)
exp.fulfill()
}
task.resume()
XCTWaiter.wait(for: [exp], timeout: 100)
}
回答18:
An example for a sample "GET" request is given below.
let urlString = "YOUR_GET_URL"
let yourURL = URL(string: urlstring)
let dataTask = URLSession.shared.dataTask(with: yourURL) { (data, response, error) in
do {
let json = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers)
print("json --- \(json)")
}catch let err {
print("err---\(err.localizedDescription)")
}
}
dataTask.resume()
回答19:
Swift 5
Nobody has mentioned using the URL-loading constructor Data(contentsOf:):
private func loadDataIntoUI(from url: URL) {
DispatchQueue.global(qos: .userInitiated).async { [weak self] in
if let data = try? Data(contentsOf: url) {
DispatchQueue.main.async {
// TODO: Update UI with data
}
}
}
}
来源：https://stackoverflow.com/questions/24016142/how-to-make-an-http-request-in-swift