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godot-docs/classes/class_json.rst
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.. Generated automatically by doc/tools/makerst.py in Godot's source tree.
.. DO NOT EDIT THIS FILE, but the JSON.xml source instead.
.. The source is found in doc/classes or modules/<name>/doc_classes.
.. _class_JSON:
JSON
====
**Inherits:** :ref:`RefCounted<class_RefCounted>` **<** :ref:`Object<class_Object>`
Helper class for creating and parsing JSON data.
Description
-----------
The ``JSON`` enables all data types to be converted to and from a JSON string. This useful for serializing data to save to a file or send over the network.
:ref:`stringify<class_JSON_method_stringify>` is used to convert any data type into a JSON string.
:ref:`parse<class_JSON_method_parse>` is used to convert any existing JSON data into a :ref:`Variant<class_Variant>` that can be used within Godot. If successfully parsed, use :ref:`get_data<class_JSON_method_get_data>` to retrieve the :ref:`Variant<class_Variant>`, and use ``typeof`` to check if the Variant's type is what you expect. JSON Objects are converted into a :ref:`Dictionary<class_Dictionary>`, but JSON data can be used to store :ref:`Array<class_Array>`\ s, numbers, :ref:`String<class_String>`\ s and even just a boolean.
**Example**
::
var data_to_send = ["a", "b", "c"]
var json = JSON.new()
var json_string = json.stringify(data_to_send)
# Save data
# ...
# Retrieve data
var error = json.parse(json_string)
if error == OK:
var data_received = json.get_data()
if typeof(data_received) == TYPE_ARRAY:
print(data_received) # Prints array
else:
print("Unexpected data")
else:
print("JSON Parse Error: ", json.get_error_message(), " in ", json_string, " at line ", json.get_error_line())
Methods
-------
+---------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`Variant<class_Variant>` | :ref:`get_data<class_JSON_method_get_data>` **(** **)** |const| |
+---------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`int<class_int>` | :ref:`get_error_line<class_JSON_method_get_error_line>` **(** **)** |const| |
+---------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`String<class_String>` | :ref:`get_error_message<class_JSON_method_get_error_message>` **(** **)** |const| |
+---------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`Error<enum_@GlobalScope_Error>` | :ref:`parse<class_JSON_method_parse>` **(** :ref:`String<class_String>` json_string **)** |
+---------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`String<class_String>` | :ref:`stringify<class_JSON_method_stringify>` **(** :ref:`Variant<class_Variant>` data, :ref:`String<class_String>` indent="", :ref:`bool<class_bool>` sort_keys=true, :ref:`bool<class_bool>` full_precision=false **)** |
+---------------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
Method Descriptions
-------------------
.. _class_JSON_method_get_data:
- :ref:`Variant<class_Variant>` **get_data** **(** **)** |const|
Returns the :ref:`Variant<class_Variant>` containing the data of a successful :ref:`parse<class_JSON_method_parse>`.
**Note:** It will return ``Null`` if the last call to parse was unsuccessful or :ref:`parse<class_JSON_method_parse>` has not yet been called.
----
.. _class_JSON_method_get_error_line:
- :ref:`int<class_int>` **get_error_line** **(** **)** |const|
Returns ``0`` if the last call to :ref:`parse<class_JSON_method_parse>` was successful, or the line number where the parse failed.
----
.. _class_JSON_method_get_error_message:
- :ref:`String<class_String>` **get_error_message** **(** **)** |const|
Returns an empty string if the last call to :ref:`parse<class_JSON_method_parse>` was successful, or the error message if it failed.
----
.. _class_JSON_method_parse:
- :ref:`Error<enum_@GlobalScope_Error>` **parse** **(** :ref:`String<class_String>` json_string **)**
Attempts to parse the ``json_string`` provided.
Returns an :ref:`Error<enum_@GlobalScope_Error>`. If the parse was successful, it returns ``OK`` and the result can be retrieved using :ref:`get_data<class_JSON_method_get_data>`. If unsuccessful, use :ref:`get_error_line<class_JSON_method_get_error_line>` and :ref:`get_error_message<class_JSON_method_get_error_message>` for identifying the source of the failure.
----
.. _class_JSON_method_stringify:
- :ref:`String<class_String>` **stringify** **(** :ref:`Variant<class_Variant>` data, :ref:`String<class_String>` indent="", :ref:`bool<class_bool>` sort_keys=true, :ref:`bool<class_bool>` full_precision=false **)**
Converts a :ref:`Variant<class_Variant>` var to JSON text and returns the result. Useful for serializing data to store or send over the network.
**Note:** The JSON specification does not define integer or float types, but only a *number* type. Therefore, converting a Variant to JSON text will convert all numerical values to :ref:`float<class_float>` types.
**Note:** If ``full_precision`` is true, when stringifying floats, the unreliable digits are stringified in addition to the reliable digits to guarantee exact decoding.
Use ``indent`` parameter to pretty stringify the output.
**Example output:**
::
## JSON.stringify(my_dictionary)
{"name":"my_dictionary","version":"1.0.0","entities":[{"name":"entity_0","value":"value_0"},{"name":"entity_1","value":"value_1"}]}
## JSON.stringify(my_dictionary, "\t")
{
"name": "my_dictionary",
"version": "1.0.0",
"entities": [
{
"name": "entity_0",
"value": "value_0"
},
{
"name": "entity_1",
"value": "value_1"
}
]
}
.. |virtual| replace:: :abbr:`virtual (This method should typically be overridden by the user to have any effect.)`
.. |const| replace:: :abbr:`const (This method has no side effects. It doesn't modify any of the instance's member variables.)`
.. |vararg| replace:: :abbr:`vararg (This method accepts any number of arguments after the ones described here.)`
.. |constructor| replace:: :abbr:`constructor (This method is used to construct a type.)`
.. |static| replace:: :abbr:`static (This method doesn't need an instance to be called, so it can be called directly using the class name.)`
.. |operator| replace:: :abbr:`operator (This method describes a valid operator to use with this type as left-hand operand.)`