我如何获取文件的绝对路径

import os

file_path = "example.txt"
abs_path = os.path.abspath(file_path)
print(abs_path)

const path = require("path");

const file_path = "example.txt";
const abs_path = path.resolve(file_path);
console.log(abs_path);

import java.nio.file.Path;
import java.nio.file.Paths;

public class Main {
    public static void main(String[] args) {
        Path file_path = Paths.get("example.txt");
        Path abs_path = file_path.toAbsolutePath();
        System.out.println(abs_path);
    }
}

using System;
using System.IO;

class MainClass {
    public static void Main (string[] args) {
        string file_path = "example.txt";
        string abs_path = Path.GetFullPath(file_path);
        Console.WriteLine(abs_path);
    }
}