SampleApp.MainForm.GetFilesByExtensions C# (CSharp) Method

        public static IEnumerable<FileInfo> GetFilesByExtensions(DirectoryInfo dir, params string[] extensions)
        {
            if (extensions == null)
                throw new ArgumentNullException("extensions");
            IEnumerable<FileInfo> files = dir.EnumerateFiles();
            return files.Where(f => extensions.Contains(f.Extension));
        }