# download(_:willSend:redirectResponse:) Sent when the download object determines that it must change URLs in order to continue loading a request. ``` optional func download(_ download: NSURLDownload, willSend request: URLRequest, redirectResponse: URLResponse?) -> URLRequest? ``` ## Parameters `download` The URL download object sending the message. `request` The proposed redirected request. The delegate should inspect the redirected request to verify that it meets its needs, and create a copy with new attributes to return to the connection if necessary. `redirectResponse` The URL response that caused the redirect. May be `nil` in cases where this method is not being sent as a result of involving the delegate in redirect processing. ## Return Value The actual URL request to use in light of the redirection response. The delegate may copy and modify `request` as necessary to change its attributes, return `request` unmodified, or return `nil`. ## Discussion If the delegate wishes to cancel the redirect, it should call the `download` object’s [`cancel()`](/documentation/Foundation/NSURLDownload/cancel()) method. Alternatively, the delegate method can return `nil` to cancel the redirect, and the download will continue to process. This has special relevance in the case where `redirectResponse` is not `nil`. In this case, any data that is loaded for the download will be sent to the delegate, and the delegate will receive a [`downloadDidFinish(_:)`](/documentation/Foundation/NSURLDownloadDelegate/downloadDidFinish(_:)) or [`download(_:didFailWithError:)`](/documentation/Foundation/NSURLDownloadDelegate/download(_:didFailWithError:)) message, as appropriate. ### Special Considerations The delegate can receive this message as a result of transforming a request’s URL to its canonical form, or for protocol-specific reasons, such as an HTTP redirect. The delegate implementation should be prepared to receive this message multiple times. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)