SpeakFriend.FileUpload.FileUploadContent.GetFileSelect C# (CSharp) 메소드

        private FileSelect GetFileSelect(Panel panel)
        {
            var fileSelects = panel.Controls.OfType<FileSelect>();
            if (fileSelects.Count() != 1)
                throw new InvalidOperationException(
                    "The SelectTemplate must contain exactly one FileSelect control.");
            return fileSelects.First();
        }