Alamofire网络提取的完成处理程序

本文介绍了Alamofire网络提取的完成处理程序的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我正在尝试创建一个函数，该函数将返回通过解析JSON创建的自定义对象列表。我正在使用AlamoFire下载内容。我写了这个函数，成功后创建了一个要返回的位置数组。但是，回报总是为零。我的代码如下：

I am attempting to create a function which will return a list of custom objects, created from parsing JSON. I am using AlamoFire to download the content. I have written this function which, on success, creates an array of locations to be returned. However, the returns are always nil. My code is below:

func fetchLocations() -> [Location]? { var locations : [Location]? Alamofire.request(.GET, myURL) .responseJSON { response in switch response.result { case .Success(let data): locations = createMapLocations(data) case .Failure(let error): print("Request failed with error: \(error)") } } return locations }

我非常肯定问题是功能在网络请求之前返回做完了。我是Swift的新手，不确定如何处理这个问题。任何帮助将不胜感激！

I am pretty positive the issue is that the functioning is returning before the network request is complete. I am new to Swift, and unsure how to handle this. Any help would be appreciated!

推荐答案

您可以阅读有关闭包/完成处理程序的更多信息 developer.apple/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Closures .html 或谷歌。

You can read more about closures/ completion handlers developer.apple/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Closures.html or google.

func fetchLocations(completionHandler: (locations: [Location]?, error: NSError) -> ()) -> () { var locations : [Location]? Alamofire.request(.GET, myURL) .responseJSON { response in switch response.result { case .Success(let data): locations = createMapLocations(data) completionHandler(locations, error: nil) case .Failure(let error): print("Request failed with error: \(error)") completionHandler(locations: nil, error: error) } } }

用法

fetchLocations(){ data in if(data.locations != nil){ //do something witht he data }else{ //Handle error here print(data.error) } }