斯威夫特3.0

通过一个小抽象 https://github.com/daltoniam/swiftHTTP

例子

    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)")
    }

在Swift 4.1和Xcode 9.4.1中。

JSON POST方法示例。要检查互联网连接，从https://developer.apple.com/library/archive/samplecode/Reachability/Introduction/Intro.html#//apple_ref/doc/uid/DTS40007324-Intro-DontLinkElementID_2添加Reachability.h & .m文件

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()

    }

}

如果你有兴趣在SharedClass中使用这个函数

//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() {

}

最后像这样调用这个函数....

SharedClass.sharedInstance.postRequestFunction(apiName: "Your API name", parameters: parameters) { (success, error, result) in
    print(result!)
    if success {
        //Your code here
    } else {
        print(error?.localizedDescription ?? "")
    }
}

另一个选择是Alamofire库，它提供了可链请求/响应方法。

https://github.com/Alamofire/Alamofire

提出请求

import Alamofire

Alamofire.request(.GET, "http://httpbin.org/get")

响应处理

Alamofire.request(.GET, "http://httpbin.org/get", parameters: ["foo": "bar"])
         .response { request, response, data, error in
              print(request)
              print(response)
              print(error)
          }

使用URLSession + Swift

只是补充cezar的答案，如果你想使用苹果的URLSession类进行web请求，有多种方法来完成任务

简单的GET请求与URL 简单的GET请求与URL和参数 简单的GET请求与错误处理的URL 简单的POST请求与URL，参数与错误处理

1. 简单的GET请求与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()
    }

注意:请确保您必须在pList中为http请求添加“NSAppTransportSecurity”键

<key>NSAppTransportSecurity</key>
<dict>
<key>NSAllowsArbitraryLoads</key>
<true/>
</dict>

2. 简单的GET请求与URL和参数

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.简单的GET请求与错误处理的URL

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. 简单的POST请求与URL，参数与错误处理。

func simplePostRequestWithParamsAndErrorHandling(){
        let configuration = URLSessionConfiguration.default
        configuration.timeoutIntervalForRequest = 30
        configuration.timeoutIntervalForResource = 30
        let 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()
    }

谢谢你的建议!!

我调用json登录按钮点击

@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()
}

在这里，我为参数创建了一个单独的字典。

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.

我已经完成了HTTP请求两种方法GET和POST与JSON解析的方式:

在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