Close the Python.NET script engine

[Davider]

The following code, using the Python.NET component to execute a Python script, can be executed successfully.
However, the script engine is not closed. Here is a demonstration of the operation.


Where should this line of code be placed? I'm stuck!
PythonEngine.Shutdown(); 

Thanks in advance for any suggestions and help.
 

Code:

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// script "PythonNET_Test.cs"
/*/ r %dll%\PyNet\Python.Runtime.dll /*/

using System;
using Python.Runtime;

class Program
{
    public static void Main()
    {
        Person someone = new Person();
        someone.FirstName = "John";
        someone.LastName = "Doe";
        someone.Age = 21;
        object age = PythonInterop.RunPythonCodeAndReturn(@"
someone.Age=someone.Age+3;
hisAge=someone.Age
", someone, "someone", "hisAge");
        Console.WriteLine("His age has changed to: " + age.ToString());
    }

    public class Person
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public int Age { get; set; }
    }
    
    public class PythonInterop
    {
        public static void Initialize()
        {
            string pythonDll = @"C:\Users\YourUserNameHere\AppData\Local\Programs\Python\Python38\python38.dll";
            Environment.SetEnvironmentVariable("PYTHONNET_PYDLL", pythonDll);
            
            PythonEngine.Initialize();
        }
        
        public static object RunPythonCodeAndReturn(string pycode, object parameter, string parameterName, string returnedVariableName)
        {
            object returnedVariable = new object(); 
            Initialize(); 
            using (Py.GIL()) 
            {
                using (var scope = Py.CreateScope()) 
                {
                    scope.Set(parameterName, parameter.ToPython());
                    scope.Exec(pycode);

                    returnedVariable = scope.Get<object>(returnedVariableName); 
                    return returnedVariable;
                }
            }
            PythonEngine.Shutdown(); 
        }
    }
}

[Gintaras]

Use try-finally. Or class Pynet from https://www.libreautomate.com/forum/show...p?tid=7484

[Davider]

pythonnet engine is an invisible process. I execute #1 C# code in QM. The first execution is successful. However, the macro fails to terminate in the second execution, leading to QM crashing.

---

By using the Pynet class in the link below, the engine can exit properly. However, I am not sure how to add the following function to that class.
https://www.libreautomate.com/forum/show...5#pid36975

public static object RunPythonCodeAndReturn(string pycode, object parameter, string parameterName, string returnedVariableName)
        {
            try
            {
                object returnedVariable = new object();
                Initialize();
                using (Py.GIL())
                {
                    using (var scope = Py.CreateScope())
                    {
                        scope.Set(parameterName, parameter.ToPython());
                        scope.Exec(pycode);
                        
                        returnedVariable = scope.Get<object>(returnedVariableName);
                        return returnedVariable;
                    }
                }
            }
            catch (Exception)
            {
                throw;
            }
        }

---

Another code! It would be fantastic if it could be added to the Pynet class.

Code:

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public dynamic? ExecuteScript<T>(string scriptFile, string className, string functionName, List<object> paramset)
{
    T? result = default;
    try
    {
        // Location of all the python scripts in the project. lets get the python file we are specifying in the function param
        string file = $"{Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location)}\\PythonScripts\\{scriptFile}.py";

        // This is initalized in the program.cs, but just want to make sure it's initialized in case something happens
        if (!PythonEngine.IsInitialized)
        {
            PythonEngine.Initialize();
            Py.GIL();
        }

        using (var scope = Py.CreateScope())
        {
            // Our returned PythonObject from the python function call
            PyObject? pythonReturn;
            // Get the python file as raw text
            string code = File.ReadAllText(file);
            // Compile the code/file
            var scriptCompiled = PythonEngine.Compile(code, file);
            // Execute the compiled python so we can start calling it
            scope.Execute(scriptCompiled);

            // Lets get an instance of the class in python
            PyObject pythonClass = scope.Get(className);

            // Add parameters to the function?
            if (paramset != null && paramset.Count > 0)
            {
                // This is an array of python parameters passed into a function
                PyObject[] pyParams = new PyObject[paramset.Count];

                // Loop through our incoming c# list of parameters and create PythonObject array .
                for (int i = 0; i < paramset.Count; i++)
                {
                    pyParams[i] = paramset[i].ToPython();
                }
                // Call the  function on the class with parameters
                pythonReturn = pythonClass.InvokeMethod(functionName, pyParams);
            }
            else // We aren't using parameters here
                 // Call the  function on the class
                pythonReturn = pythonClass.InvokeMethod(functionName);

            // Lets convert our returned pythonObject to that of the object type (C#)
            object? netObject = pythonReturn.AsManagedObject(typeof(object));

            // A special case of when we want a list back. We will convert the object to the specific type in the caller function
            if (typeof(T) == typeof(IList<object>))
            {
                object[] something = pythonReturn.As<object[]>();
                return something;
            }

            // Convert the c# object to that of what we expect to be returned,. string/int/bool/class
            if (netObject != null)
                // convert the returned string to managed string object
                result = (T)netObject;
        }
        return result;
    }
    catch (Exception)
    {
        // Handle your exceptions here
        throw;
    }
}