When is a NSURLResponse not a NSHTTPURLResponse?

iphone ios nsurlconnection
CornPuff picture CornPuff · Sep 13, 2011 · Viewed 8.1k times · Source

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 the NSURLConnections not return NSHTTPURLResponse?

I'm worried that if I simply downcast the response, I'm introducing buggy code.

For instance, is it OK to do this without checking isKindOfClass?

- (NSURLRequest *)connection:(NSURLConnection *)connection willSendRequest:(NSURLRequest *)request redirectResponse:(NSURLResponse *)redirectResponse
{
 NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse*)redirectResponse;
 // do stuff
}

Answer

Nekto picture Nekto · Sep 13, 2011

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.

Related questions

NSURLConnection and Basic HTTP Authentication in iOS

I need to invoke an initial GET HTTP request with Basic Authentication. This would be the first time the request is sent to the server and I already have the username & password so there's no need for a challenge …

Read More
how to use sendAsynchronousRequest:queue:completionHandler:

Two part question Part one: I am trying to create an ASynchronous request to my database. I am currently doing it Synchronously however I want to learn both ways to better my understanding of whats going on. Currently I have …

Read More
Xml parsing in iOS tutorial

Hi i'm creating an app which have to print a value in label from an xml file in server.I tried reading some of documentation under google search..but i can't find it...Does any one know simple tutorial or …

Read More