c# 写入字节流文件

public void WriteData(byte[] data)
        {
            string path = AppDomain.CurrentDomain.BaseDirectory;
            path += "\\dat";
            if (!string.IsNullOrEmpty(path))
            {
                if (!Directory.Exists(path))
                {
                    Directory.CreateDirectory(path);
                }
                path = path + "\\" + filename + ".dat";
                if (!File.Exists(path))
                {
                    FileStream fs = File.Create(path);
                    fs.Close();
                }
                if (File.Exists(path))
                {
                    FileStream file = new FileStream(path, FileMode.Append);//以追加的形式打开文件
                    file.Write(data, 0, data.Length);//写入byte[]型数据
                    file.Flush();
                    file.Close();
                }
            }
        }

其二

FileStream fs = new FileStream(path, FileMode.Append); //初始化FileStream对象
                    BinaryWriter bw = new BinaryWriter(fs); //创建BinaryWriter对象
                    //FileStream file = new FileStream(path, FileMode.Append);//以追加的形式打开文件
                    foreach (var item in list)
                    {
                        bw.Write(item);//写入byte[]型数据
                    }
                    //file.Flush();
                    bw.Close();
                    fs.Close();