To count number of files in the folder.

Here is a simple example showing how you can count the number of files in folder.

public static int numberOfFiles;
public static int fileCount(string filePath, string file_Extension)
        {
            string[] fileDir = Directory.GetFiles(filePath);
            foreach (string files in fileDir)
            {
                string fileName = files.Substring(filePath.Length + 1);
                string[] fileExtension = fileName.Split('.');
                if (fileExtension[1] == file_Extension)
                {
                   numberOfFiles  = numberOfFiles + 1;
                }
            }
            return numberOfFiles;
        }