When is a NSURLResponse not a NSHTTPURLResponse?

Question

I\'ve seen a lot of code, including Apple\'s SimpleURLConnections sample, that simply cast any NSURLResponse to a NSHTTPURLResponse. If it is always a NSHTTPURLResponse why do t

Answer 1

The safer way to do it is with introspection.

if ([response isKindOfClass:[NSHTTPURLResponse class]]) {
   NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse*)redirectResponse;
   // do stuff
}

Answer 2

It is ok if you are sure that your connection runs via HTTP protocol:

An NSHTTPURLResponse object represents a response to an HTTP URL load request. It’s a subclass of NSURLResponse that provides methods for accessing information specific to HTTP protocol responses.

If you are connecting via FTP, for example, then casting NSURLResponse to NSHTTPURLResponse will be incorrect.