iOS Swift Alamofire cachePolicy

Question

在Alamofire版本3中，我将NSURLRequest.CachePolicy.returnCacheDataDontLoad用于请求缓存

let URLRequest = NSMutableURLRequest(url: URL(string: url)!)
    URLRequest.cachePolicy = NSURLRequest.CachePolicy.returnCacheDataDontLoad
    Alamofire.request(URLRequest){...}

但是如何在Alamofire 4和swift 3中使用cachePolicy呢？

谢谢

Answer 1

我找遍了所有地方，最后得到了这个：

    let TheURL = DEFAULT_APP_URL + "api/getList?Id="+ID
    let urlString = NSURL(string: TheURL)
    var mutableURLRequest = URLRequest(url: urlString! as URL)
    mutableURLRequest.httpMethod = "GET"
    mutableURLRequest.setValue("application/json", forHTTPHeaderField: "Content-Type")
    mutableURLRequest.cachePolicy = NSURLRequest.CachePolicy.returnCacheDataElseLoad


    Alamofire.request(mutableURLRequest)
        .responseJSON
       {....}

Answer 2

这是我的一段工作代码。

    private static func request(_ showHud: Bool = true, urlString: String,
                            httpMethod: HTTPMethod,
                            parameters: [String : Any] = [:],
                            headers: [String : Any] = [:],
                            success : @escaping SuccessBlock,
                            failure : @escaping ErrorBlock) {
    var additionalHeaders: HTTPHeaders?
    additionalHeaders = headers as? HTTPHeaders
    guard let url = URL(string: urlString) else { return }

    var urlRequest = URLRequest(url: url)
    if !(NetworkReachabilityManager()?.isReachable ?? false) {
        urlRequest.cachePolicy = .returnCacheDataDontLoad
    } else {
        showIndicator(showHud)
    }
    urlRequest.allHTTPHeaderFields = additionalHeaders
    urlRequest.httpMethod = httpMethod.rawValue
    do {
        urlRequest = httpMethod == .get ? try URLEncoding.default.encode(urlRequest, with: parameters) : try JSONEncoding.default.encode(urlRequest, with: parameters)
    } catch {
        failure(NSError(localizedDescription: "Something went wrong!"))
    }
    Alamofire.request(urlRequest).responseObject { (response: DataResponse<ResponseHandler>) in
        parseResponse(response, success: success, failure: failure)
    }
}

关键是在从缓存加载数据之前，我检查了互联网连接。如果互联网可用，我显示加载器，它加载api，如果没有，它从缓存中给我数据。