即使缓存策略设置为 ReloadIgnoringLocalAndRemoteCacheData，Alamofire 也会从缓存中加载

Question

我在 Alamofire 中将缓存策略设置为请求以忽略本地缓存。

然后我用网络连接加载 viewcontroller，然后我断开网络连接，关闭应用程序并再次运行它。

现在没有显示没有网络可用错误（即 alamofire 不创建 nserror 对象）创建，而不是应用程序运行s 就好像请求成功从缓存中获取数据一样 obviously.And 奇怪的是当我尝试使用

检查缓存数据时

NSURLCache.sharedURLCache().cachedResponseForRequest(request)

即使数据来自缓存，也返回 nil ..

我可以阻止缓存响应的唯一方法是执行 NSURLCache.sharedURLCache().removeAllCachedResponses()

    let request = NSURLRequest(URL: NSURL(string: url)!, cachePolicy: NSURLRequestCachePolicy.ReloadIgnoringLocalAndRemoteCacheData, timeoutInterval: 100)

    Alamofire.manager.request(method, request, parameters:params)
    .responseJSON { (request, response, data, error) in
        if let anError = error {
            if anError.code == NSURLErrorNotConnectedToInternet {
                UIAlertView(title: "Alert", message: "No Network Connection Available", delegate: nil, cancelButtonTitle: "ok").show()
            }    

        } else if let data: AnyObject = data {
            println(NSURLCache.sharedURLCache().cachedResponseForRequest(request))
 //prints nil

    }

} 
}

我想做的是仅在网络连接不可用时才从缓存中加载数据，比如限制离线 mode.How 来做到这一点？

Answer 1

我在一个项目中使用了这种方式并且它正在工作：

let mutableURLRequest = NSMutableURLRequest(URL: SERVICEURL)
mutableURLRequest.HTTPMethod = "POST"

mutableURLRequest.HTTPBody = self.createJson()
mutableURLRequest.setValue("application/json", forHTTPHeaderField: "Content-Type")
mutableURLRequest.cachePolicy = NSURLRequestCachePolicy.ReloadIgnoringCacheData

request(mutableURLRequest).validate().responseJSON{ response in...

希望对您有所帮助。

Answer 2

ReloadIgnoringLocalAndRemoteCacheData 未实现。

https://developer.apple.com/reference/foundation/nsurlrequestcachepolicy/1408722-reloadignoringlocalandremotecach

http://nshipster.com/nsurlcache/

更新：从iOS13开始，实现了NSURLRequest.CachePolicy.reloadRevalidatingCacheData和NSURLRequest.CachePolicy.reloadIgnoringLocalAndRemoteCacheData。 https://developer.apple.com/documentation/ios_ipados_release_notes/ios_13_release_notes

Answer 3

感谢 @FábioSalata 我这样解决了我的问题。

 var req = URLRequest(url: URL(string: "<URL>")!)
 req.httpMethod = "GET"
 req.setValue("application/json", forHTTPHeaderField: "Content-Type")
 req.setValue("<Auth KEY>", forHTTPHeaderField:"Authorization" )
 req.cachePolicy = NSURLRequest.CachePolicy.reloadIgnoringCacheData

 Alamofire.request(req).validate().responseJSON { response in ...

即使缓存策略设置为 ReloadIgnoringLocalAndRemoteCacheData，Alamofire 也会从缓存中加载

Alamofire loading from cache even when cache policy set to ReloadIgnoringLocalAndRemoteCacheData

caching

ios

swift

alamofire