如何使用 IronPython 从 Python 文件中获取变量

Question

I want to get a variable from my Python file and write it in the console here is what i have tried:

main.py

myVar = "Hello There"

program.cs

using System;
using IronPython.Hosting;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            var py = Python.CreateEngine();

            var pythonVariable = py.ExecuteFile("main.py");
            Console.WriteLine(pythonVariable);

            Console.Read();

        }
    }
}

I would expect the output to be 'Hello There' but I get this: 'Microsoft.Scripting.Hosting.ScriptScope'

Answer 1

The output you get is hinting what you have to look for. ExecuteFile returns a ScriptScope which contains all the variables defined in the executed Python code.

In order to retrieve a specific variable from it you need to use GetVariable or TryGetVariable (if the variable may not exist in the file), eg:

using System;
using IronPython.Hosting;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            var py = Python.CreateEngine();

            var pythonVariable = py.ExecuteFile("main.py").GetVariable<string>("myVar");
            Console.WriteLine(pythonVariable);

            Console.Read();

        }
    }
}

Note that I used the generic version of GetVariable to convert it to a string immediately. The non-generic version returns a dynamic object, choosing which one you need depends on how you intend to use the variable

Answer 2

Follow this procedure and it should work, Be sure to have file in the right place. I don't see you setting any variables Do that and just follow the code:

var engine = Python.CreateEngine(); // Extract Python language engine from their grasp
            var source = engine.CreateScriptSourceFromFile(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "myPython.py"));
            var scope = engine.CreateScope();
            source.Execute(scope);
            var theVar = scope.GetVariable("myVar");

            Console.WriteLine(theVar);
            Console.ReadKey();