RichTextBox的LoadFile函数的用法

            string path = "";            openFileDialog.Filter = "所有文件|*.*|记事本文件|*.txt|doc文档|*.doc";            openFileDialog.InitialDirectory = "D:\\";            if (DialogResult.OK == openFileDialog.ShowDialog())            {                path = openFileDialog.FileName;                FileStream fs = new FileStream(path, FileMode.OpenOrCreate);                RichTextBoxStreamType streamType;                //文件扩展名                string fileExt = path.Substring(path.LastIndexOf('.') + 1);                switch (fileExt)                {                    case "txt": // 文本文件                        streamType = RichTextBoxStreamType.PlainText; break;                    case "rtf": // 写字板                        streamType = RichTextBoxStreamType.RichText; break;                    case "srt": // 影片字幕                        streamType = RichTextBoxStreamType.UnicodePlainText; break;                    case "lrc": // 歌词文件                        streamType = RichTextBoxStreamType.PlainText; break;                    case "xml": // XML文件                        streamType = RichTextBoxStreamType.PlainText; break;                    default: // 默认类型                        streamType = RichTextBoxStreamType.PlainText; break;                }                rtbContent.LoadFile(fs, streamType);            }