.. _direct_dotnet:

Microsoft .NET
--------------
Load a 64-bit C# library (a .NET Framework) in 64-bit Python (view the
:ref:`C# source code <dotnet-lib>`). Include the ``'net'`` argument to
indicate that the ``.dll`` file is for the .NET Framework.
*To load the 32-bit library in 32-bit Python use* ``'/dotnet_lib32.dll'``.

.. invisible-code-block: pycon

   >>> SKIP_IF_32BIT() or SKIP_IF_NO_PYTHONNET()

.. code-block:: pycon

   >>> from msl.loadlib import LoadLibrary
   >>> from msl.examples.loadlib import EXAMPLES_DIR
   >>> net = LoadLibrary(EXAMPLES_DIR + '/dotnet_lib64.dll', 'net')

.. tip::

   ``'clr'`` is an alias for ``'net'`` and can also be used as the `libtype`

.. attention::
   To configure `pythonnet` to use the .NET Core runtime, you must either
   run

   .. code-block:: python

      from pythonnet import load
      load("coreclr")

   or define a ``PYTHONNET_RUNTIME=coreclr`` environment variable

   .. code-block:: python

      import os
      os.environ["PYTHONNET_RUNTIME"] = "coreclr"

   before :class:`~msl.loadlib.load_library.LoadLibrary` is called.
   To use the Mono runtime, replace ``"coreclr"`` with ``"mono"``.

The :ref:`dotnet_lib64 <dotnet-lib>` library contains a reference to the
``DotNetMSL`` module (which is a C# namespace), the ``StaticClass`` class,
the ``StringManipulation`` class and the System_ namespace

Create an instance of the ``BasicMath`` class in the ``DotNetMSL`` namespace
and call the ``multiply_doubles`` method

.. code-block:: pycon

   >>> bm = net.lib.DotNetMSL.BasicMath()
   >>> bm.multiply_doubles(2.3, 5.6)
   12.879999...

Create an instance of the ``ArrayManipulation`` class in the ``DotNetMSL``
namespace and call the ``scalar_multiply`` method

.. code-block:: pycon

   >>> am = net.lib.DotNetMSL.ArrayManipulation()
   >>> values = am.scalar_multiply(2., [1., 2., 3., 4., 5.])
   >>> values
   <System.Double[] object at ...>
   >>> [val for val in values]
   [2.0, 4.0, 6.0, 8.0, 10.0]

Use the ``reverse_string`` method in the ``StringManipulation`` class to
reverse a string

.. code-block:: pycon

   >>> net.lib.StringManipulation().reverse_string('abcdefghijklmnopqrstuvwxyz')
   'zyxwvutsrqponmlkjihgfedcba'

Use the static ``add_multiple`` method in the ``StaticClass`` class to add
five integers

.. code-block:: pycon

   >>> net.lib.StaticClass.add_multiple(1, 2, 3, 4, 5)
   15

One can create objects from the System_ namespace,

.. code-block:: pycon

   >>> System = net.lib.System

for example, to create a 32-bit signed integer,

.. code-block:: pycon

   >>> System.Int32(9)
   <System.Int32 object at ...>

or, a one-dimensional Array_ of the specified Type_

.. code-block:: pycon

   >>> array = System.Array[int](list(range(10)))
   >>> array
   <System.Int32[] object at ...>
   >>> list(array)
   [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
   >>> array[0] = -1
   >>> list(array)
   [-1, 1, 2, 3, 4, 5, 6, 7, 8, 9]

.. invisible-code-block: pycon

   >>> net.cleanup()  # See: https://github.com/pythonnet/pythonnet/issues/1683

.. _System: https://docs.microsoft.com/en-us/dotnet/api/system
.. _Array: https://docs.microsoft.com/en-us/dotnet/api/system.array?view=net-6.0
.. _Type: https://docs.microsoft.com/en-us/dotnet/api/system.type?view=net-6.0