我正在将CodeIgniter与MongoDB一起使用，并希望使用ID来获取数据，该ID保存在MongoDB中，我执行了打印数据的查询，但是我不知道要打印什么数据
我执行此查询
$query=$this->mongo_db->where('posts', array('_id' => new \MongoDB\BSON\ObjectID($id)));
并获得此结果没有任何数据
Mongo_db Object
(
[CodeIgniter:Mongo_db:private] => User Object
(
[benchmark] => CI_Benchmark Object
(
[marker] => Array
(
[total_execution_time_start] => 1559113613.9923
[loading_time:_base_classes_start] => 1559113613.9923
[loading_time:_base_classes_end] => 1559113614.0023
[controller_execution_time_( User / single )_start] => 1559113614.0023
)
)
[hooks] => CI_Hooks Object
(
[enabled] =>
[hooks] => Array
(
)
[_objects:protected] => Array
(
)
[_in_progress:protected] =>
)
[config] => CI_Config Object
(
[config] => Array
(
[base_url] => http://localhost/chronicle/
[index_page] => index.php
[uri_protocol] => REQUEST_URI
[url_suffix] =>
[language] => english
[charset] => UTF-8
[enable_hooks] =>
[subclass_prefix] => MY_
[composer_autoload] =>
[permitted_uri_chars] => a-z 0-9~%.:_\-
[enable_query_strings] =>
[controller_trigger] => c
[function_trigger] => m
[directory_trigger] => d
[allow_get_array] => 1
[log_threshold] => 0
[log_path] =>
[log_file_extension] =>
[log_file_permissions] => 420
[log_date_format] => Y-m-d H:i:s
[error_views_path] =>
[cache_path] =>
[cache_query_string] =>
[encryption_key] =>
[sess_driver] => files
[sess_cookie_name] => ci_session
[sess_expiration] => 7200
[sess_save_path] =>
[sess_match_ip] =>
[sess_time_to_update] => 300
[sess_regenerate_destroy] =>
[cookie_prefix] =>
[cookie_domain] =>
[cookie_path] => /
[cookie_secure] =>
[cookie_httponly] =>
[standardize_newlines] =>
[global_xss_filtering] =>
[csrf_protection] =>
[csrf_token_name] => csrf_test_name
[csrf_cookie_name] => csrf_cookie_name
[csrf_expire] => 7200
[csrf_regenerate] => 1
[csrf_exclude_uris] => Array
(
)
[compress_output] =>
[time_reference] => local
[rewrite_short_tags] =>
[proxy_ips] =>
[mongo_db] => Array
(
[active_config_group] => default
[default] => Array
(
[settings] => Array
(
[auth] => 1
[debug] => 1
[return_as] => array
[auto_reset_query] => 1
)
[connection_string] =>
[connection] => Array
(
[host] => 127.0.0.1
[port] => 27017
[user_name] => admin
[user_password] => admin
[db_name] => centralchronicle
[db_options] => Array
(
)
)
[driver] => Array
(
)
)
)
)
[is_loaded] => Array
(
[0] => D:\xampp\htdocs\chronicle\application\config/mongo_db.php
)
[_config_paths] => Array
(
[0] => D:\xampp\htdocs\chronicle\application\
)
)
[log] => CI_Log Object
(
[_log_path:protected] => D:\xampp\htdocs\chronicle\application\logs/
[_file_permissions:protected] => 420
[_threshold:protected] => 0
[_threshold_array:protected] => Array
(
)
[_date_fmt:protected] => Y-m-d H:i:s
[_file_ext:protected] => php
[_enabled:protected] => 1
[_levels:protected] => Array
(
[ERROR] => 1
[DEBUG] => 2
[INFO] => 3
[ALL] => 4
)
)
[utf8] => CI_Utf8 Object
(
)
[uri] => CI_URI Object
(
[keyval] => Array
(
)
[uri_string] => User/single/5ced0e57ed4e3e0fbc017e19
[segments] => Array
(
[1] => User
[2] => single
[3] => 5ced0e57ed4e3e0fbc017e19
)
[rsegments] => Array
(
[1] => User
[2] => single
[3] => 5ced0e57ed4e3e0fbc017e19
)
[_permitted_uri_chars:protected] => a-z 0-9~%.:_\-
[config] => CI_Config Object
(
[config] => Array
(
[base_url] => http://localhost/chronicle/
[index_page] => index.php
[uri_protocol] => REQUEST_URI
[url_suffix] =>
[language] => english
[charset] => UTF-8
[enable_hooks] =>
[subclass_prefix] => MY_
[composer_autoload] =>
[permitted_uri_chars] => a-z 0-9~%.:_\-
[enable_query_strings] =>
[controller_trigger] => c
[function_trigger] => m
[directory_trigger] => d
[allow_get_array] => 1
[log_threshold] => 0
[log_path] =>
[log_file_extension] =>
[log_file_permissions] => 420
[log_date_format] => Y-m-d H:i:s
[error_views_path] =>
[cache_path] =>
[cache_query_string] =>
[encryption_key] =>
[sess_driver] => files
[sess_cookie_name] => ci_session
[sess_expiration] => 7200
[sess_save_path] =>
[sess_match_ip] =>
[sess_time_to_update] => 300
[sess_regenerate_destroy] =>
[cookie_prefix] =>
[cookie_domain] =>
[cookie_path] => /
[cookie_secure] =>
[cookie_httponly] =>
[standardize_newlines] =>
[global_xss_filtering] =>
[csrf_protection] =>
[csrf_token_name] => csrf_test_name
[csrf_cookie_name] => csrf_cookie_name
[csrf_expire] => 7200
[csrf_regenerate] => 1
[csrf_exclude_uris] => Array
(
)
[compress_output] =>
[time_reference] => local
[rewrite_short_tags] =>
[proxy_ips] =>
[mongo_db] => Array
(
[active_config_group] => default
[default] => Array
(
[settings] => Array
(
[auth] => 1
[debug] => 1
[return_as] => array
[auto_reset_query] => 1
)
[connection_string] =>
[connection] => Array
(
[host] => 127.0.0.1
[port] => 27017
[user_name] => admin
[user_password] => admin
[db_name] => centralchronicle
[db_options] => Array
(
)
)
[driver] => Array
(
)
)
)
)
[is_loaded] => Array
(
[0] => D:\xampp\htdocs\chronicle\application\config/mongo_db.php
)
[_config_paths] => Array
(
[0] => D:\xampp\htdocs\chronicle\application\
)
)
)
[router] => CI_Router Object
(
[config] => CI_Config Object
(
[config] => Array
(
[base_url] => http://localhost/chronicle/
[index_page] => index.php
[uri_protocol] => REQUEST_URI
[url_suffix] =>
[language] => english
[charset] => UTF-8
[enable_hooks] =>
[subclass_prefix] => MY_
[composer_autoload] =>
[permitted_uri_chars] => a-z 0-9~%.:_\-
[enable_query_strings] =>
[controller_trigger] => c
[function_trigger] => m
[directory_trigger] => d
[allow_get_array] => 1
[log_threshold] => 0
[log_path] =>
[log_file_extension] =>
[log_file_permissions] => 420
[log_date_format] => Y-m-d H:i:s
[error_views_path] =>
[cache_path] =>
[cache_query_string] =>
[encryption_key] =>
[sess_driver] => files
[sess_cookie_name] => ci_session
[sess_expiration] => 7200
[sess_save_path] =>
[sess_match_ip] =>
[sess_time_to_update] => 300
[sess_regenerate_destroy] =>
[cookie_prefix] =>
[cookie_domain] =>
[cookie_path] => /
[cookie_secure] =>
[cookie_httponly] =>
[standardize_newlines] =>
[global_xss_filtering] =>
[csrf_protection] =>
[csrf_token_name] => csrf_test_name
[csrf_cookie_name] => csrf_cookie_name
[csrf_expire] => 7200
[csrf_regenerate] => 1
[csrf_exclude_uris] => Array
(
)
[compress_output] =>
[time_reference] => local
[rewrite_short_tags] =>
[proxy_ips] =>
[mongo_db] => Array
(
[active_config_group] => default
[default] => Array
(
[settings] => Array
(
[auth] => 1
[debug] => 1
[return_as] => array
[auto_reset_query] => 1
)
[connection_string] =>
[connection] => Array
(
[host] => 127.0.0.1
[port] => 27017
[user_name] => admin
[user_password] => admin
[db_name] => centralchronicle
[db_options] => Array
(
)
)
[driver] => Array
(
)
)
)
)
[is_loaded] => Array
(
[0] => D:\xampp\htdocs\chronicle\application\config/mongo_db.php
)
[_config_paths] => Array
(
[0] => D:\xampp\htdocs\chronicle\application\
)