Alamofire 在 Swift 中无法正确执行

Question

我有一个 Alamofire 请求，假设下载一个文件，但它不会执行它自己的代码。这是 Alamofire 代码：

var testNumbers: Int = 0
var testString: String = "Hi"
Alamofire.download(.GET, "http://www.sayweee.com/admin_groupbuy/export_deal_orders/71w4o?format=csv") { temporaryURL, response in
            
            let fileManager = NSFileManager.defaultManager()
            let directoryURL = fileManager.URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)[0]
            let pathComponent = response.suggestedFilename  

            print("1")
            testNumbers = 1  

            print(directoryURL.URLByAppendingPathComponent(pathComponent!)) 

            print("blah")
            testString = "blah"
            print("2")
            testNumbers = 2  

            return directoryURL.URLByAppendingPathComponent(pathComponent!)
            
        }
print(testNumbers)
print(testString)

执行此代码将在控制台中打印：

 0
 Hi

我很确定这意味着{} 中的代码没有被执行。我读过另一个关于这个主题的文章，并了解到 Alamofire 是“异步的”，正如他们在this post 中所说的那样。我试图摆脱viewDidLoad() 方法和viewDidAppear() 方法中的所有内容，并确保我没有任何无限循环。即使在那之后，结果也是一样的。关于为什么会发生在我身上的任何想法或建议？我试图在这里和谷歌上查看，但我只找到了一篇与这个主题相关的帖子，就是上面链接的那个。

Answer 1

首先我把你的代码放到Demo Alamofire中运行，发现运行结果和你说的一样，如下图： 0 Hi 2015-12-30 14:31:29.873 iOS Example[3966:142688] App Transport Security has blocked a cleartext HTTP (http://) resource load since it is insecure. Temporary exceptions can be configured via your app's Info.plist file.

根据提示你会看到问题： App Transport Security has blocked a cleartext HTTP (http://) resource load since it is insecure. Temporary exceptions can be configured via your app's Info.plist file.

解决方法如下（在项目文件“info.plist”中）： In project's "info.plist" file to add a "NSAppTransportSecurity" dictionary, an element is added in the dictionary.Key for "NSAllowsArbitraryLoads", the value is: YES, make it back to the HTTP protocol for the time being.

问题解决链接：

Transport security has blocked a cleartext HTTP

最终结果如下：

0 Hi 1 file:///Users/yangshebing/Library/Developer/CoreSimulator/Devices/151CB429-29B3-46D0-AFF5-37D5B8D9E4FC/data/Containers/Data/Application/756A32D1-64C5-48CF-B652-D3009D80780D/Documents/71w4o.html blah 2

具体问题可以去查询苹果官方文档，查询iOS9 ATS适配问题。

希望能帮到你！