AFNetworking缺少setCompletionBlock ios swift

Question

我尝试从url下载带有进度的pdf文件。一切都好。但我找不到setCompletionBlock，为什么？ 这是我的工作代码：

println("progress: \(0.0)")

    let request: NSURLRequest = NSURLRequest(URL: NSURL(string: document.link)!)
    let operation: AFURLConnectionOperation = AFHTTPRequestOperation(request: request)
    let paths: NSArray = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.UserDomainMask, true)
    let filePath: NSString = paths.objectAtIndex(0).stringByAppendingPathComponent("pdf_\(document.id).pdf")
    operation.outputStream = NSOutputStream(toFileAtPath: filePath, append: false)

    operation.setDownloadProgressBlock({(bytesRead, totalBytesRead, totalBytesExpectedToRead) -> Void in

        var total: CGFloat = CGFloat(totalBytesRead) / CGFloat(totalBytesExpectedToRead)
        println("progress: \(total)")


    })

    //operation.setCompletionBlock ... can't found this block?!

    operation.start()

Answer 1

您正在将AFHTTPRequestOperation投射到AFURLConnectionOperation：

let operation: AFURLConnectionOperation = AFHTTPRequestOperation(request: request)

但setCompletionBlockWithSuccess中定义的是AFHTTPRequestOperation，而不是AFURLConnectionOperation。

相反，只需让operation成为AFHTTPRequestOperation：

let operation = AFHTTPRequestOperation(request: request)

然后它会成功识别setCompletionBlockWithSuccess。