C#

Luc Pattyn wrote:

if the number embedded in the filename uses a fixed format with leading zeroes the alphabetical order is the numeric order too, so no special comparer would be needed.

public void filecount(string file)
{
int x;
int y;
string file;

int filepaths = Directory.GetFiles(@"C:\Desktop\Request", "*txt").Length;
x = filepaths +1;

StreamWriter sw;
sw = File.CreateText(@"C:\Desktop\Request\Text" +y +".txt");
file = Path.GetFileName(@"C:\Desktop\Request\Text" +y +".txt").ToString;
sw.Close();

return file;
}

public void btn_Click(object sender, EventArgs e)
{
filecount(file);
}

string[] logfiles = Directory.GetFiles(@"../Files/", @"Text*.txt");
Array.Sort(logfiles, CompareFileNumbers);

int highestNumber = int.Parse(Regex.Match(logfiles[0], @"(\d+)").Value);

public static int CompareFileNumbers(string fileA, string fileB)
{
	Regex regexNumber = new Regex(@"(\d+)");

	int fileNumberA = int.Parse(regexNumber.Match(fileA).Value);
	int fileNumberB = int.Parse(regexNumber.Match(fileB).Value);

	return -fileNumberA.CompareTo(fileNumberB); // the miuns sign will sort descending
}