URL会话保存图像

Question

快速问答。我想从网址中提取下载的图像，并将其保存到UI图像。

我该怎么做呢？

fileprivate func beginDownload() {

        let url = URL(string: "URL")!

        let configuration = URLSessionConfiguration.default
        let operationQueue = OperationQueue()
        let urlSession = URLSession(configuration: configuration, delegate: self, delegateQueue: operationQueue)

        let downloadTask = urlSession.downloadTask(with: url)

        downloadTask.resume()
}

以下是我的URL会话协议存根：

func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didWriteData bytesWritten: Int64, totalBytesWritten: Int64, totalBytesExpectedToWrite: Int64) {
        print(totalBytesWritten, totalBytesExpectedToWrite)

    }

    func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didFinishDownloadingTo location: URL) {

        print("Finished dowloading file")
    }

Answer 1

您需要从委托方法urlSession(_:downloadTask:didFinishDownloadingTo:)中创建的下载location加载图像

class Request: NSObject {

    func getPicture() {
        let url = URL(string: "https://media.tractorsupply.com/is/image/TractorSupplyCompany/1305371?$456$")!
        let session = URLSession(configuration: .default, 
                                 delegate: self, 
                                 delegateQueue: nil)
        session.downloadTask(with: url).resume()
    }

}

extension Request: URLSessionDownloadDelegate {

    func urlSession(_ session: URLSession, 
                    downloadTask: URLSessionDownloadTask, 
                    didFinishDownloadingTo location: URL) {
        guard let data = try? Data(contentsOf: location), 
              let image = UIImage(data: data) else { return }
        print(image)
    }

}

Request().getPicture()