C#.Net 3.5使用LINQ替换文件扩展名的代码

using System;
using System.IO;
using System.Linq;

class Program
{
    static void Main()
    {
        string filePath = @"C:\example\file.txt";
        string newExtension = ".pdf";

        string newFilePath = ReplaceFileExtension(filePath, newExtension);

        Console.WriteLine($"Original file path: {filePath}");
        Console.WriteLine($"New file path: {newFilePath}");
    }

    static string ReplaceFileExtension(string filePath, string newExtension)
    {
        string fileNameWithoutExtension = Path.GetFileNameWithoutExtension(filePath);
        string directory = Path.GetDirectoryName(filePath);

        string newFilePath = Path.Combine(directory, $"{fileNameWithoutExtension}{newExtension}");

        return newFilePath;
    }
}