压缩解压object对象

Question

我有两个函数，保存、读取object对象到磁盘文件。文件平均大小200M。
大神给封装下。保存和读取文件的时候压缩下。。
压缩幅度越大越好，尽量把文件压缩的小点。 public static void SaveObject(object o, string filePath)
        {
            if (!Directory.Exists(filePath)) { Directory.CreateDirectory(Path.GetDirectoryName(filePath)); }
            using (FileStream fs = new FileStream(filePath, FileMode.Create))
            {
                BinaryFormatter bf = new BinaryFormatter();
                bf.Serialize(fs, o);
            }
        }        public static object ReadObject(string filePath)
        {
            object o;
            using (FileStream fs = new FileStream(filePath, FileMode.Open))
            {
                BinaryFormatter bf = new BinaryFormatter();
                o = bf.Deserialize(fs) as object;
            }
            return o;
        }

Answer 1

zip压缩啊…… SharpZipLib
    public class ZipHelper
    {
        public static void Zip(string zipFilePath, string passWord = null, params string[] files)
        {
            using (var fStream = File.Create(zipFilePath))
            {
                using (var zoStream = new ZipOutputStream(fStream))
                {
                    if (!string.IsNullOrWhiteSpace(passWord))
                    {
                        zoStream.Password = passWord;
                    }
                    var buffer = new byte[4096];
                    foreach (var file in files)
                    {
                        var entry = new ZipEntry(Path.GetFileName(file));
                        zoStream.PutNextEntry(entry);
                        using (var fs = File.OpenRead(file))
                        {
                            int sourceBytes;
                            do
                            {
                                sourceBytes = fs.Read(buffer, 0, buffer.Length);
                                zoStream.Write(buffer, 0, sourceBytes);
                            } while (sourceBytes > 0);
                        }
                    }
                    zoStream.Finish();
                }
            }
        }        public static IList<string> UnZip(string zipFilePath, string unZipDirectory, string passWord = null)
        {
            IList<string> list = new List<string>();
            using (var ziStream = new ZipInputStream(File.OpenRead(zipFilePath)))
            {
                if (!string.IsNullOrWhiteSpace(passWord))
                {
                    ziStream.Password = passWord;
                }
                ZipEntry theEntry;
                while ((theEntry = ziStream.GetNextEntry()) != null)
                {
                    if (!Directory.Exists(unZipDirectory))
                    {
                        Directory.CreateDirectory(unZipDirectory);
                    }
                    string path = Path.Combine(unZipDirectory, theEntry.Name);
                    using (var streamWriter = File.Create(path))
                    {
                        list.Add(path);
                        var data = new byte[2048];
                        while (true)
                        {
                            var size = ziStream.Read(data, 0, data.Length);
                            if (size > 0)
                            {
                                streamWriter.Write(data, 0, size);
                            }
                            else
                            {
                                break;
                            }
                        }
                    }
                }
            }
            return list;
        }
    }

Answer 2

object要能保存为文件,还要能读回来还原,有一个前提是
这个必须是成员都必须是简单数据类型,不然还包括一些引用,那些引用对象可能早不存在了,可能就完全错误了    public static byte[] Object2Bytes(object obj)
    {
        byte[] buff = new byte[Marshal.SizeOf(obj)];
        IntPtr ptr = Marshal.UnsafeAddrOfPinnedArrayElement(buff, 0);
        Marshal.StructureToPtr(obj, ptr, true);
        return buff;
    }    public static object Bytes2Object(byte[] buff, Type typ)
    {
        IntPtr ptr = Marshal.UnsafeAddrOfPinnedArrayElement(buff, 0);
        return Marshal.PtrToStructure(ptr, typ);
    }

Answer 3

保存的是list<T>这样的数据。应该可以压缩保存的吧

Answer 4

通用压缩算法调用简单，但是压缩效率可能达不到预期。
压缩本质是对byte[]进行处理
所以最高效的方法是自行对object的特性进行分析
根据数据特征进行压缩。
比如，存入的是一组相邻的时间（Datetime）
要压缩效果好，
就是存一个开始时间，后续的数据存与起始时间的差值