Error Domain=NSURLErrorDomain Code=-1002 "unsupported URL" UserInfo=0x7f9dc278aa60 {NSUnderlyingError=0x7f9dc2565dc0 "unsupported URL", NSErrorFailingURLStringKey=myUrl, NSErrorFailingURLKey=myUrl, NSLocalizedDescription=unsupported URL}

url有错误：

原因一：url前没有加http://