Does -dataWithContentsOfURL: of NSData work in a background thread?

Question

Does -dataWithContentsOfURL: of NSData work in a background thread?

Answer 1

No, it doesn't.

In order to get data from URL asynchronously you should use the NSURLRequest and NSURLConnection approach.

You will have to implement the NSURLConnectionDelegate methods:

-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response;
-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data;
-(void)connectionDidFinishLoading:(NSURLConnection *)connection;
-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error;