Objective-C Authentication - html

Question

I am currently writing an iPhone application that will push a username and password to a website to retrieve the HTML source code of the page which loads. I include login information in NSString *post.
When I NSLog the _responseData instance variable in the connectionDidFinishLoading method, the console prints a long series of eight digit hexadecimal numbers which I assume are some type of address or encrypted HTML (3c21444f 43545950 45206874 6d6c2050 55424c49 4320222d 2f2f5733...).
What should I do to convert/decrypt the addresses into HTML code or otherwise retrieve the HTML code of the webpage which loads?
My ViewController conforms to the NSURLConnectionDelegate protocol and includes the following code:
#interface ViewController : UIViewController<NSURLConnectionDelegate>
{
NSMutableData *_responseData;
}
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
// A response has been received, this is where we initialize the instance var you created
// so that we can append data to it in the didReceiveData method
// Furthermore, this method is called each time there is a redirect so reinitializing it
// also serves to clear it
_responseData = [[NSMutableData alloc] init];
NSLog(#"Received response");
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
// Append the new data to the instance variable you declared
NSLog(#"Received data");
[_responseData appendData:data];
}
- (NSCachedURLResponse *)connection:(NSURLConnection *)connection
willCacheResponse:(NSCachedURLResponse*)cachedResponse {
// Return nil to indicate not necessary to store a cached response for this connection
return nil;
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
// The request is complete and data has been received
// You can parse the stuff in your instance variable now
//NSString *html=[NSString stringWithContentsOfURL:[NSURL URLWithString:#"https://grades.bsd405.org/Pinnacle/Gradebook/InternetViewer/GradeSummary.aspx?&EnrollmentId=770595&TermId=127463&ReportType=0&StudentId=114040"] encoding:NSASCIIStringEncoding error:nil];
NSLog(#"Finished loading");
//PRINT HTML:
NSLog(#"Data: %#",_responseData);
}
- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
// The request has failed for some reason!
// Check the error var
NSLog(#"Failed to load");
}
- (IBAction)goPressed:(UIButton *)sender {
NSString *post = #"__LASTFOCUS&__EVENTTARGET&__EVENTARGUMENT&__VIEWSTATE=/wEPDwUJNTkxNzI3MDIzD2QWAmYPZBYCA
gMPZBYGAgEPZBYCAgkPZBYCAgEPZBYIAgMPFgIeB1Zpc2libGVoZAIFDxYCHwBoZAIHDxYCHwBoZAIJDxYCHgVzdH
lsZQUjdmVydGljYWwtYWxpZ246bWlkZGxlO2Rpc3BsYXk6bm9uZTtkAgMPDxYCHwBoZGQCBQ9kFghmD2QWAgINDxY
CHgVjbGFzcwUQc2luZ2xlU2Nob29sTGlzdBYCAgEPZBYCAgEPEGQPFgFmFgEQBQ5EZWZhdWx0IERvbWFpbgUIUGlu
bmFjbGVnZGQCAg9kFgICEw9kFgICAQ9kFgICAQ8QZGQWAGQCBw8PFgIeBFRleHQFIFBpbm5hY2xlIEdyYWRlIDIwM
TIgV2ludGVyIEJyZWFrZGQCCA8PFgIfAwU3Q29weXJpZ2h0IChjKSAyMDEzIEdsb2JhbFNjaG9sYXIuICBBbGwgcm
lnaHRzIHJlc2VydmVkLmRkZP/l6irI9peZfyqpKjk3fwLuEbos&__EVENTVALIDATION=/wEWBgKjnbqUCQLnksmg
AQKTpbWbDgLB5+KIBAL4xb20BAK20ZqiCel6sQLBsF1W3XHOxpgq+tJj+Rx2&ctl00$ContentPlaceHolder$Use
rname=TESTUSERNAME&ctl00$ContentPlaceHolder$Password=TESTPASSWORD&ctl00$ContentPlaceHolde
r$lstDomains=Pinnacle&ctl00$ContentPlaceHolder$LogonButton=Sign
in&PageUniqueId=2dacba26-
bb0d-412f-b06a-e02caf039c4b";
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:#"%d", [postData length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:[NSURL URLWithString:#"https://grades.bsd405.org/Pinnacle/Gradebook/Logon.aspx?ReturnUrl=%2fPinnacle%2fGradebook%2fDefault.aspx"]];
[request setHTTPMethod:#"POST"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:postData];
[NSURLConnection connectionWithRequest:request delegate:self];
}

Answer 1

The NSLog of your NSData displays the object's description, which a hexadecimal string of the underlying binary data:
3c21444f 43545950 45206874 6d6c2050 55424c49 4320222d 2f2f5733 ...
Translates to a string of
<!DOCTYPE html PUBLIC "-//W3 ...
To get the NSString from the NSData, you do:
NSString *string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];