How to call a python function in a c# program and get its result?

Question

C++ / C#

You need to write a program in c # (or at least in c ++) so that you can load a python script, call a function from it, transfer an array (well, or other data) to it, the function worked and returned the result to the main program. The variant with calling the interpreter and passing parameters to it is not suitable. You need speed, as much as possible of course

Answer 1

c#

using Process process = Process.Start(new ProcessStartInfo {
  FileName = "python",
  Arguments = @"path\pyscript.py",
  UseShellExecute = false,
  RedirectStandardInput = true,
  RedirectStandardOutput = true
});

int[] arr = { 1, 2, 3, 4, 5, 6 };

using BinaryWriter writer = new BinaryWriter(process.StandardInput.BaseStream);
Array.ForEach(arr, writer.Write);
writer.Flush();

using BinaryReader reader = new BinaryReader(process.StandardOutput.BaseStream);
int result = reader.ReadInt32();

Console.WriteLine(result);

Console.ReadKey(false);

python:

import os
import sys

stdin = sys.stdin.buffer
stdout = sys.stdout.buffer


def get_int_list():
    stdin.seek(0, os.SEEK_END)
    n = stdin.tell() // 4
    arr = [0] * n

    for i in range(n):
        arr[i] = int.from_bytes(stdin.read(4), byteorder='little')

    return arr


def write_int(i: int):
    stdout.write(i.to_bytes(4, byteorder='little'))


nums = get_int_list()

result = sum(nums)

write_int(result)

Result: 21

Answer 2

You can look towards IronPython. Here is an example: https://www.red-gate.com/simple-talk/dotnet/net-fr...

Answer 3

If you need speed, as much as possible, then one of the options is to implement this algorithm in C # or C ++.
As a last resort, connect python as a library and work with it: https://habr.com/en/post/168083/

Answer 4

Calling an interpreter is rather slow. Instead of this method, it makes sense to use Python.NET
Or the method from the documentation
https://docs.python.org/3/extending/embedding.html