ObjectId.createFromBase64.txt

.. _ObjectId.createFromBase64:

===========================
ObjectId.createFromBase64()
===========================

.. default-domain:: mongodb

.. contents:: On this page
   :local:
   :backlinks: none
   :depth: 1
   :class: singlecol

Definition
----------

Creates an :term:`ObjectId` from a base64 value.

Compatibility
-------------

This method is available in deployments hosted in the following environments: 

.. include:: /includes/fact-environments-atlas-only.rst

.. include:: /includes/fact-environments-onprem-only.rst

Syntax
------

.. method:: ObjectId.createFromBase64( <base64String> [ , <subType> ]  )

Method Fields
~~~~~~~~~~~~~

The method accepts the following fields:

.. list-table::
   :header-rows: 1
   :widths: 20 20 80

   * - Field
     - Type
     - Description

   * - ``base64String``
     - String
     - Specifies a 16 character base64 value. For example,
       ``"SGVsbG8gV29ybGQh"``.

   * - ``subType``
     - Integer
     - Optional. Specifies a binary subtype.

       .. include:: /includes/binary-sub-types.rst

Examples
--------

The following examples show how to add an object identifier to a
document using ``ObjectId.createFromBase64()`` and how the object
identifier appears in the output when retrieved.

Create Collection Containing Document with Base64 Number
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The following example creates a collection named
``objectIdentifierValuesFromBase64``:

.. code-block:: javascript
   :emphasize-lines: 3

   db.objectIdentifierValuesFromBase64.insertOne( {
      _id: 0,
      objectIdentifierValue: ObjectId.createFromBase64( "SGVsbG8gV29ybGQh" )
   } )

The ``objectIdentifierValue`` field contains the object identifier
created from the base64 string specified in
``ObjectId.createFromBase64()``.

Retrieve Document from Collection with Object Identifier
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The following example retrieves the document:

.. code-block:: javascript

   db.objectIdentifierValuesFromBase64.findOne( { _id: 0 } )

Example output:

.. code-block:: javascript
   :copyable: false
   :emphasize-lines: 3

   {
      _id: 0,
      objectIdentifierValue: ObjectId("48656c6c6f20576f726c6421")
   }