How to get data back from webserver with NSMutableURLRequest - iphone

Question

I try to build an app for user that enter his data and this data will be post to a webserver for save in a Database. This web server returns some data back like Id or something else.
How I can receive the data the webserver returns back?
The transfer works already with NSMutableURLRequest. But I search for a sollution to read the answer from the web server and display it on a label.

Answer 1

Have a look at the delegate methods of NSURLConnection.

Answer 2

Example of how it could be done. Original source
NSString *post = #"key1=val1&key2=val2";
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:#"%d", [postData length]];
NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
[request setURL:[NSURL URLWithString:#"http://www.someurl.com"]];
[request setHTTPMethod:#"POST"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:postData];
NSURLConnection *conn=[[NSURLConnection alloc] initWithRequest:request delegate:self];
if (conn)
{
receivedData = [[NSMutableData data] retain];
}
else
{
// inform the user that the download could not be made
}
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
[receivedData setLength:0];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
[receivedData appendData:data];
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
// do something with the data
// receivedData is declared as a method instance elsewhere
NSLog(#"Succeeded! Received %d bytes of data",[receivedData length]);
NSString *aStr = [[NSString alloc] initWithData:receivedData encoding:NSASCIIStringEncoding];
NSLog(aStr);
// release the connection, and the data object
[receivedData release];
}