请问定位到的值如何赋值到kilometres ？

Question

 NSString *oreillyAddress = @"南昌深圳市场";
                    CLGeocoder *myGeocoder = [[CLGeocoder alloc] init];
                    [myGeocoder geocodeAddressString:oreillyAddress completionHandler:^(NSArray *places, NSError *error) {
                        if ([places count] > 0 && error == nil) {
                            NSLog(@"Found %lu place(s).", (unsigned long)[places count]);
                            CLPlace *firstPlace = [places objectAtIndex:0];
                            NSLog(@"Longitude = %f", firstPlace.location.coordinate.longitude);
                            NSLog(@"Latitude = %f", firstPlace.location.coordinate.latitude);
                        }
                        else if ([places count] == 0 && error == nil) {
                            NSLog(@"Found no places.");
                        } else if (error != nil) {
                            NSLog(@"An error occurred = %@", error);
                        }
                    }];
                    float kilometres =50.00;

Answer 1

  float kilometres =50.00;
 NSString *oreillyAddress = @"南昌深圳农批市场";
                    CLGeocoder *myGeocoder = [[CLGeocoder alloc] init];
                    [myGeocoder geocodeAddressString:oreillyAddress completionHandler:^(NSArray *places, NSError *error) {
                        if ([places count] > 0 && error == nil) {
                            NSLog(@"Found %lu place(s).", (unsigned long)[places count]);
                            CLPlace *firstPlace = [places objectAtIndex:0];
                            NSLog(@"Longitude = %f", firstPlace.location.coordinate.longitude);
kilometres = firstPlace.location.coordinate.longitude；
                            NSLog(@"Latitude = %f", firstPlace.location.coordinate.latitude);
                        }
                        else if ([places count] == 0 && error == nil) {
                            NSLog(@"Found no places.");
                        } else if (error != nil) {
                            NSLog(@"An error occurred = %@", error);
                        }
                    }];
                      NSLog(@"kilometres  %@", kilometres );这样的话在还未执行完block，kilometres 直接输出为null了