C# 文件分块读取和写入

     #region 文件分块读取
        /// 

        /// 文件分块读取
        /// 
        /// 文件路径
        /// 每一次读取的文件大小
        public static void FileRead()
        {
            int length = 0;
            byte[] buffer = new byte[4*1024];           
            using (FileStream fileStream = new FileStream(@"F:\BaiDuYun\WPF\2.XAML基础.wmv", FileMode.Open, FileAccess.Read))
            {
                using (BinaryReader br = new BinaryReader(fileStream))
                {           
                    while ((length = fileStream.Read(buffer, 0, buffer.Length))>0)
                    {
                      
                        using (FileStream writeFileStream = new FileStream(@"F:\BaiDuYun\WPF\12.XAML基础.wmv", FileMode.Append, FileAccess.Write))
                        {
                            writeFileStream.Write(buffer,0,length);
                        }
                    }
                }
                            
            }                   
        }
        #endregion