// C# Extension Method

// Doc: https://csharp-extension.com/en/method/1002017/fileinfo-getdirectoryname

​

// @nuget: Z.ExtensionMethods

​

using System;

public class Program

{

    public static void Main()

    {

        string FileName = "folder\\subfolder\\test.txt";

        // C# Extension Method: FileInfo - GetDirectoryName

        string dirName = FileName.ToFileInfo().GetDirectoryName();

        Console.WriteLine(dirName);

    }

}