c# richbox

//先保存为文件

            string  filename =  @"C:\Example.rtf" ;
            RichTextBox.SaveFile(filename);


            //然后读取文件转成btye[]
            byte [] output =  new  byte [0];
            try
            {

                FileStream fs =  new  FileStream(filename, FileMode.Open, FileAccess.Read);
                BinaryReader reader =  new  BinaryReader(fs);
                reader.BaseStream.Seek(0, SeekOrigin.Begin);
                output = reader.ReadBytes(( int )reader.BaseStream.Length);
            }
            catch  { }

            //读进rtf
            RichTextBox.Clear();
            RichTextBox.LoadFile(filename);