iOS定位服务与地图开发(3)---地理信息编码查询

- (IBAction)geocodeQuery:(id)sender
{
    NSString *queryStr = nil;
    // 从界面文本框输入地址字符串
    if (_textField.text == nil || [_textField.text length] == 0) {
        return ;
    }
    
    CLGeocoder *geocoder = [[CLGeocoder alloc] init];
    [geocoder geocodeAddressString:queryStr completionHandler:^(NSArray *placemarks, NSError *error) {
        NSLog(@"查询记录数:%i",[placemarks count]);
        if ([placemarks count] > 0) {
            
            CLPlacemark *placemark = [placemarks objectAtIndex:0];
            CLLocationCoordinate2D coordinate = placemark.location.coordinate;
            
            // 生成经纬度字符串
            NSString *strCoordinate = [NSString stringWithFormat:@"经度：%3.5f,纬度：%3.5f",coordinate.latitude,coordinate.longitude];
            
            NSDictionary *addressDict = placemark.addressDictionary;
            
            NSString *address = [addressDict objectForKey:(NSString *)kABPersonAddressStreetKey];
            address = address == nil ? @"" : address;
            
            NSString *state = [addressDict objectForKey:(NSString *)kABPersonAddressStateKey];
            
            state = state == nil ? @"" : state;
            
            NSString *city = [addressDict objectForKey:(NSString *)kABPersonAddressCityKey];
            
            city = city == nil ? @"" : city;
            
            //  获取地标对应的可读的文字信息，一般返回到UI显示
            NSString *streetInfo = [NSString stringWithFormat:@"%@\n%@\n%@\n%@\n",strCoordinate,state,address,city];
        }
    }];
}

 CLRegion *region = [[CLRegion alloc] initCircularRegionWithCenter:_currLocation.coordinate radius:1000.0f identifier:@"GeocodeRegion"];
    CLGeocoder *geocoder = [[CLGeocoder alloc] init];
    [geocoder geocodeAddressString:queryStr inRegion:region completionHandler:^(NSArray *placemarks, NSError *error) {
        .......
    }];