AEURLDownload

Block-based asynchronous URL downloading

AEURLDownload makes it easy to asynchronously download a URL to the filesystem, just like the NSURLDownload class that is available in desktop Cocoa. Even better, it uses blocks and chooses a safe, temporary location automatically.

• Start a download by calling +downloadWithRequest:completionHandler:
• When the download completes your completion handler block is called on the main thread.
• The downloaded file is passed to you as an NSURL file URL that is valid only for the duration of the completion handler's execution. You must copy it to a new location if you want to hold onto it.
• Watch out for non-200 status codes like 404, 500, or 304. You can test for these by calling -statusCode on the NSURLResponse that is passed to you in the completion block. If the status is not 200, you probably got something you weren't expecting.
• Cancel an in-progress download by calling -cancel on the object that is returned from +downloadWithRequest:completionHandler:. You can safely ignore that object if you don't want cancellation; you don't need to retain it until the download finishes.

Why not NSURLConnectionDownloadDelegate?

NSURLConnectionDownloadDelegate would be perfect if it worked. It's only available for Newsstand apps as of this writing.

How do I use it?

[AEURLDownload downloadWithRequest:request 
                 completionHandler:^(NSURLResponse *response, NSURL *destinationURL, NSError *error) {
    // Handle the downloaded file or error.
}];