How to send HTTP get requests and HTTP asynchronous requests in iOS applications

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    
    _data = [[NSMutableData alloc] init];
    
// Combine a search string
    NSString *urlStr = [NSString stringWithFormat:@"/s?wd=%@", @"php"];
    NSURL *url = [NSURL URLWithString:urlStr];
    
    NSURLRequest *request = [NSURLRequest requestWithURL:url];
    
//Stamp the request and define the proxy
    [NSURLConnection connectionWithRequest:request delegate:self];
    
}
 
// Return data in batches
- (void)connection:(NSURLConnection *) connection didReceiveData:(NSData *)data {
    [_data appendData:data];
    NSLog(@"%@", _data);
}
 
// The data is completely returned
- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
    NSString *dataString =  [[NSString alloc] initWithData:_data encoding:NSUTF8StringEncoding];
    NSLog(@"%@", dataString);
}