Example of a method that takes a callback method, defined as theSelector, as a parameter:
```objectivec
- (void) getURL:(NSString *)theURL theSelector:(SEL)theSelector
{
NSURL *url = [NSURL URLWithString:theURL];
ASIHTTPRequest *request = [[[ASIHTTPRequest alloc] initWithURL:url] autorelease];
[request setDelegate:self];
[request setDidFinishSelector:theSelector];
[request setDidFailSelector:@selector(onError:)];
[networkQueue addOperation:request];
[networkQueue go];
}
```
```objectivec
// Don't forget the semicolon
SEL sel = @selector(onResponseReceived:);
[self getURL:@"http://www.google.com" selector:sel];
```
```objectivec
- (void)onResponseReceived:(ASIHTTPRequest *)request {
}
```