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copied!<p>You could use an <strong>NSMutableURLRequest</strong> to access a php page that reads the ranking(s) from a mySQL database. Have the php output xml and parse the result. The following code sends a request to a php page, then parses the xml that is returned by that page. (You could also post data to a different php page to update DB entries, etc.).</p> <pre><code>//IN THE .h class (of a viewController) ... : UIViewController { //I use a label to display the data IBOutlet UILabel *label1; //Create global variable NSString *tempString; //Dataset for response from HTTP Request NSMutableData *receivedData; NSXMLParser *xmlParser; } -(void) initiateAPIConnection; @property (nonatomic, retain) NSString *tempString; @property (nonatomic, retain) UILabel *label1; @end //IN THE .h class //IN THE .m class //... @synthesize label1, tempString; //... -(void)initiateAPIConnection{ NSString *post = [NSString stringWithFormat:@"user=Chris"]; 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.yourDomain.com/yourPhpPage.php"]]; [request setHTTPMethod:@"POST"]; [request setValue:postLength forHTTPHeaderField:@"Content-Length"]; [request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"]; [request setTimeoutInterval:10.0]; //fail after 10 seconds with no response [request setHTTPBody:postData]; NSURLConnection *conn=[[[NSURLConnection alloc] initWithRequest:request delegate:self] autorelease]; if (conn){ NSLog(@"In if conn"); receivedData = [[NSMutableData data] retain]; NSLog(@"End of if conn"); } else{ UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"Conn error" message:@"No Server" delegate:nil cancelButtonTitle:@"ok" otherButtonTitles:nil]; [alert show]; [alert release]; } }//initiateAPIConnection -(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error{ UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"Connection error" message:[error localizedDescription] delegate:self cancelButtonTitle:@"ok" otherButtonTitles:nil]; [alert show]; [alert release]; } -(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response{ NSHTTPURLResponse *urlResponse = (NSHTTPURLResponse *)response; NSLog(@"%i",[urlResponse statusCode]); [receivedData setLength:0]; } -(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data{ [receivedData appendData:data]; } -(void)connectionDidFinishLoading:(NSURLConnection *)connection{ xmlParser = [[NSXMLParser alloc]initWithData:receivedData]; [xmlParser setDelegate:self]; //you may want to enable these features of NSXMLParser. [xmlParser setShouldProcessNamespaces:NO]; [xmlParser setShouldReportNamespacePrefixes:NO]; [xmlParser setShouldResolveExternalEntities:NO]; [xmlParser parse]; } //XMLdeligate methods -(void)parserDidStartDocument:(NSXMLParser *)parser{ NSLog(@"Started Parsing"); } -(void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qualifiedName attributes:(NSDictionary *)attributeDict{ NSLog(@"Started Element name: %@", elementName); } -(void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string{ NSLog(@"Found characters: %@", string); tempString = string; } -(void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName{ NSLog(@"Finished Element name: %@", elementName); //my outputted xml would have <ranking>...ValueFromDb...</ranking> in it's response if([elementName isEqualToString:@"ranking"]){ //display result in a label (you could save it to a local variable instead) label1.text = tempString; } } -(void)parserDidEndDocument:(NSXMLParser *)parser{ NSLog(@"Finished Parsing"); } //... //Don't forget to dealloc -(void)dealloc { //... [label1 release]; [tempString release]; [xmlParser release]; [receivedData release]; //... [super dealloc]; } //IN THE .m class </code></pre> <p>You'll have to work out the logic required to search the database for the user in questions ranking yourself. You can pass login information by appending (e.g.) ?user=USERNAME&pass=PASSWORD to the end of the .php file ... i.e. ...</p> <pre><code>[request setURL:[NSURL URLWithString:@"http://www.yourDomain.com/yourPhpPage.php?user=USERNAME&pass=PASSWORD"]]; </code></pre> <p>USERNAME and PASSWORD would be values read from the sandbox etc. ... you'll need to format the URLWithString (like you do with stringWithFormat)</p> <p>-Chris Allinson</p>

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