Sending post variables to iOS form - iphone

Question

I am trying to send a username and password to a website which is normally done through a form. The server however is redirecting me to a login page, which usually occurs when the username and password is wrong. The username is in the form of an email address and the password is a string.
I do currently have access to the website as the developer is away to check that the values are being processed correctly. Can anyone see any obvious errors in the code I have created below?
Please note I have removed the URL from the example code for privacy reasons.
// Validate login
-(bool)validateLogin{
// Initialize URL to be fetched
NSURL *url = [NSURL URLWithString:#"removedurl"];
NSString *post = #"username=example1%40example.com&password=example2";
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:#"%d", [postData length]];
// Initalize a request from a URL
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[url standardizedURL]];
//set url
[request setURL:url];
//set http method
[request setHTTPMethod:#"POST"];
//set request length
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
//set request content type we MUST set this value.
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
//set post data of request
[request setHTTPBody:postData];
NSLog(#"%#", [request allHTTPHeaderFields]);
//initialize a connection from request
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
_connection = connection;
//start the connection
[connection start];
return YES;
}

Answer 1

This string is not correct NSString *post = #"username=example1%40example.com&example2";
After ampersand you have to provide key=value.
#"key1=value1&key2=value2";
Example of working code:
In .h file set delegate:
#interface Controller <NSURLConnectionDataDelegate>
In .m file:
- (void)login {
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:urlString] cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:kRequestTimeOut];
request.HTTPMethod = #"POST";
NSString *params = #"key1=value1&key2=value2";
request.HTTPBody = [params dataUsingEncoding:NSUTF8StringEncoding];
_data = [NSMutableData data];
NSURLConnection *connection = [NSURLConnection connectionWithRequest:request delegate:self];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
[_data appendData:data];
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
//Parse your '_data' here.
}