pythonnet: Seamless Python and .NET Integration

Introduction

pythonnet is a powerful package that bridges the gap between Python and the .NET Common Language Runtime (CLR). It provides Python programmers with nearly seamless integration with .NET, allowing them to interact with .NET assemblies and objects directly from Python code. Conversely, .NET developers can leverage pythonnet to embed Python as a scripting engine within their .NET applications, opening up new possibilities for extensibility and dynamic behavior.

Installation

Installing pythonnet is straightforward. You can typically install it using pip or conda-forge for Python environments, and via NuGet for .NET projects.

pip install pythonnet

Or using conda-forge:

conda install -c conda-forge pythonnet

For .NET applications, you can add the pythonnet NuGet package. By default, pythonnet uses Mono on Linux and macOS, and .NET Framework on Windows. For specific runtime configurations, such as .NET Core, refer to the official documentation.

Examples

Calling .NET Code from Python

pythonnet allows CLR namespaces to be treated essentially as Python packages. You can load assemblies using clr.AddReference().

import clr
from System import String
from System.Collections import *

# Load a .NET assembly
clr.AddReference("System.Windows.Forms")
from System.Windows.Forms import Form

# Example for .NET Core runtime
from pythonnet import load
load("coreclr") # Explicitly load .NET Core
import clr

Embedding Python in .NET

To embed Python in a .NET application, you need to initialize the Python engine and manage the Global Interpreter Lock (GIL). Remember to set the Runtime.PythonDLL property or PYTHONNET_PYDLL environment variable before initialization.

using System;
using System.Collections.Generic;
using Python.Runtime;

public class Program
{
    public static void Main(string[] args)
    {
        // Set Python DLL path, e.g., "python38.dll" on Windows
        // Runtime.PythonDLL = "python38.dll"; // Uncomment and set appropriate path
        PythonEngine.Initialize();
        using (Py.GIL())
        {
            dynamic np = Py.Import("numpy");
            Console.WriteLine(np.cos(np.pi * 2));

            dynamic sin = np.sin;
            Console.WriteLine(sin(5));

            double c = (double)(np.cos(5) + sin(5));
            Console.WriteLine(c);

            dynamic a = np.array(new List<float> { 1, 2, 3 });
            Console.WriteLine(a.dtype);

            dynamic b = np.array(new List<float> { 6, 5, 4 }, dtype: np.int32);
            Console.WriteLine(b.dtype);

            Console.WriteLine(a * b);
            Console.ReadKey();
        }
    }
}

Why Use It

pythonnet offers significant advantages for developers working in both Python and .NET ecosystems. It enables seamless interoperability, allowing you to reuse existing codebases and libraries across languages. Python developers can access the vast array of .NET libraries and frameworks, while .NET developers can integrate Python's powerful scripting capabilities, data science tools, and machine learning libraries directly into their applications. This flexibility fosters greater productivity and expands the possibilities for complex application development.

Links

For more detailed information, documentation, and community support, refer to the following official resources:

• GitHub Repository
• Wiki
• Mailing List
• Gitter Chat