Question

我有一个NetworkRequest类，我的所有alamofire请求都在这里：

    class NetworkRequest {
        static let request = NetworkRequest()

        var currentRequest: Alamofire.Request?

        let dataManager = DataManager()
        let networkManager = NetworkReachabilityManager()
        let priority = DISPATCH_QUEUE_PRIORITY_DEFAULT

        func downloadData<T: Film>(slug: String, provider: String, section: String, dynamic: String, anyClass: T, completion: ([T]?) -> Void ) {
            var token: String = ""

            if LOGGED_IN == true {
                token = "\(NSUserDefaults.standardUserDefaults().valueForKey(TOKEN)!)"
            }

            let headers = [
                "Access": "application/json",
                "Authorization": "Bearer \(token)"
            ]

            let dataUrl = "\(BASE_URL)\(slug)\(provider)\(section)\(dynamic)"
            print(headers)
            print(dataUrl)

            if networkManager!.isReachable {

                currentRequest?.cancel()

                dispatch_async(dispatch_get_global_queue(priority, 0)) {

                    if let url = NSURL(string: dataUrl) {
                        let request = Alamofire.request(.GET, url, headers: headers)

                        request.validate().responseJSON { response in
                            switch response.result {
                            case .Success:
                                if let data = response.result.value as! [String: AnyObject]! {
                                    let receivedData = self.dataManager.parseDataToFilms(data, someClass: anyClass)
                                    completion(receivedData)
                                }

                            case .Failure(let error):
                                print("Alamofire error: \(error)")

                                if error.code == 1001 {
                                    self.goToNoConnectionVC()
                                }

                                print("canceled")
                            }

                        }
                    }
                }
            } else {
                goToNoConnectionVC()
            }
        }
}

我需要取消之前的downloadData请求，当新的请求启动时，尝试使用currentRequest？.cancel（）取消，但它没有帮助。

已尝试使用NSOperationsBlock取消操作，但它不会取消当前操作。

我现在阻止了UI，因此用户无法发送其他请求。但这不正确，以后会导致一些错误...

请帮忙

Answer 1

现在Alamofire 4 Alamofire.Manager.sharedInstance.session无效，您应该使用this解决方案：

let sessionManager = Alamofire.SessionManager.default 
sessionManager.session.getTasksWithCompletionHandler { dataTasks, uploadTasks, downloadTasks in 
dataTasks.forEach { $0.cancel() } 
uploadTasks.forEach { $0.cancel() } 
downloadTasks.forEach { $0.cancel() } 
}

如果您要取消（暂停，恢复）特定请求，可以查看.forEach块中的请求网址，如下所示：

dataTasks.forEach {
                if ($0.originalRequest?.url?.absoluteString == url) {
                    $0.cancel()
                }
            }

Answer 2

找到所需的解决方案：

func stopAllSessions() {
    Alamofire.Manager.sharedInstance.session.getAllTasksWithCompletionHandler { tasks in
        tasks.forEach { $0.cancel() }
    }
}

Answer 3

如果要取消请求，则需要跟踪发出的请求并尝试取消它。您可以将其存储在一个数组中，并取消存储的每个先前的请求。在您的代码中，您创建了一个请求： let request = Alamofire.request(.GET, url, headers: headers) 但是你试图取消永远不会被估价的currentRequest?.cancel()。

Answer 4

快捷键5

要取消所有请求，请使用

Alamofire.Session.default.session.getTasksWithCompletionHandler({ dataTasks, uploadTasks, downloadTasks in
        dataTasks.forEach { $0.cancel() }
        uploadTasks.forEach { $0.cancel() }
        downloadTasks.forEach { $0.cancel() }
    })

要取消具有特定网址的请求，请使用

Alamofire.Session.default.session.getTasksWithCompletionHandler({ dataTasks, uploadTasks, downloadTasks in
    dataTasks.forEach {
            if ($0.originalRequest?.url?.absoluteString == "www.google.com") {
                $0.cancel()
            }
        
    }
    uploadTasks.forEach {
        if ($0.originalRequest?.url?.absoluteString == "www.google.com") {
            $0.cancel()
        }
    }
    downloadTasks.forEach {
        if ($0.originalRequest?.url?.absoluteString == "www.google.com") {
            $0.cancel()
        }
        
    }
})

swift，alamofire取消之前的请求

4 个答案: