First steps with Python.NET

[burque505]

The PythonNET documentation available on the web can be frustratingly opaque. This example is cribbed from the one at pythonnet.github.io with significant tweaking.
 

Code:

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/*/ nuget PyNet\pythonnet; /*/
using System;
using Python.Runtime;

// create a person object
Person person = new Person("Engelbert", "Humperdinck");

// If you do not have PYTHONNET_DLL set, uncomment the line below and
// modify the path to suit your system.
// Runtime.PythonDLL = @"C:\Program Files\Python310\python310.dll";
// I don't require that line on my system.

PythonEngine.Initialize();
// acquire the GIL before using the Python interpreter
using (Py.GIL())
{
    // create a Python scope
    using dynamic scope = Py.CreateScope();
    {
        // convert the Person object to a PyObject
        PyObject pyPerson = person.ToPython();

        // create a Python variable "person"
        scope.Set("person", pyPerson);

        // the person object may now be used in Python
        scope.Exec("fullName = person.FirstName + ' ' + person.LastName");
        var pythonStrObj = scope.Eval("fullName");
        var csharpStrObj = pythonStrObj.As<string>();
        print.it(csharpStrObj );
    }
}
PythonEngine.Shutdown();

/// <summary>
/// C# Person class
/// </summary>
public class Person
{
    /// <summary>
    ///
    /// </summary>
    /// <param name="firstName"></param>
    /// <param name="lastName"></param>
    public Person(string firstName, string lastName)
    {
        FirstName = firstName;
        LastName = lastName;
    }

    /// <summary>
    /// In the Python code, use FirstName
    /// </summary>
    public string FirstName { get; set; }
    /// <summary>
    /// In the Python code, use LastName
    /// </summary>
    public string LastName { get; set; }
}

---

Here's another example, this time converting a Python list object to a C# int[]. I got the original example from this CodeProject post, and it was a little easier to mod.
 

Code:

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/*/ nuget PyNet\PythonNet; /*/
using Python.Runtime;

PythonEngine.Initialize();
using (Py.GIL()) // begin 'using'
{
    using var scope = Py.CreateScope();

    scope.Exec("number_list = [1, 2, 3, 4, 5]");
    var pythonListObj = scope.Eval("number_list");
    var csharpListObj = pythonListObj.As<int[]>();

    print.it("The numbers from python are:");
    foreach (var value in csharpListObj)
    {
        print.it(value);
    }

} // end 'using'.
PythonEngine.Shutdown();