About AFDownloadRequestOperation
AFDownloadRequestOperation is a subclass of AFHTTPRequestOperation for downloading files to a specified destination path, with progress support.
This class extends the features provided by AFHTTPRequestOperation to support file downloading. It encapsulates the logic necessary to download a file from a remote URL, with progress tracking and communication to the user.
Features
- Asynchronous downloading with progress tracking
- Ability to pause and resume downloads
- Option to set a custom download destination path
- Background downloading support (in case of app termination)
- Notification block callbacks for progress and completion events
Usage
To use AFDownloadRequestOperation, follow these steps:
- Import the AFNetworking module:
import AFNetworking
- Create an NSURLRequest object for the file you want to download:
let url = URL(string: "https://example.com/myfile.pdf") let request = URLRequest(url: url!)
- Configure an AFDownloadRequestOperation object with the request:
let operation = AFDownloadRequestOperation(request: request, targetPath: "/path/to/save/file.pdf", shouldResume: false)
- Set progress and completion block callbacks:
operation.progressBlock = { (bytesWritten, totalBytesWritten, totalBytesExpectedToWrite) in // Update UI with download progress } operation.completionBlock = { (operation, error) in if let error = error { print("Download failed: \(error.localizedDescription)") } else { print("Download completed successfully") } }
- Start the download operation:
operation.start() // or add the operation to an operation queue
Additional Options
AFDownloadRequestOperation provides additional options to customize the download behavior. Use the following properties to modify the default behavior:
- TargetPath: Set a custom download destination path. If not specified, the downloaded file will be saved in the temporary directory.
- ShouldResume: Set to true to enable resumable downloads.
- ShouldOverwrite: Set to true to overwrite an existing downloaded file at the target path.
operation.shouldOverwrite = true
Modify these properties before starting the download operation.
Conclusion
AFDownloadRequestOperation is a powerful class that facilitates the downloading of files with progress tracking and other customization options. By following the provided usage guide, you can easily integrate file downloads into your application.