Delete.cs

public void Delete(string fileToDelete, string host, string username, string password)
{
    try
    {
        using (var sftpClient = new SftpClient(host, username, password))
        {
            sftpClient.Connect();

            sftpClient.DeleteFile(fileToDelete);

            sftpClient.Disconnect();
        }
    }
    catch (Exception e)
    {
        Console.WriteLine(e.Message);
    }
}