using System;

using System.Text;

using System.Linq;

using System.IO;

public class Program

{

    public static void Main()

    {

        int filenumber = 0;

        string content = "";

        StringBuilder sb = new StringBuilder();

        for(var i = 0; i < 2000; i++)

        {

            sb.Append("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");

        }

        content = sb.ToString();

        do

        {

            string filename = $"f:\\dump\\{filenumber.ToString().PadLeft(8,'0')}.txt";

            Console.WriteLine("writing...");

            Console.WriteLine(filename);

            filenumber++;

        }

        while(true);

    }

}

​