C#中关于zip压缩解压帮助类的封装 附源码下载

c#下压缩解压，主要是用第三方类库进行封装的。icsharpcode.sharpziplib.dll类库，链接地址为你官方下载链接。压缩主要是用流的方式进行压缩的。

压缩文件及文件夹。文件压缩很简单，把待压缩的文件用流的方式读到内存中，然后放到压缩流中。就可以了。文件夹就稍微麻烦下了。因为要把待压缩的文件夹解压后保留文件夹文件的层次结构。所以我的实现方式就是 递归遍历文件夹中的文件。计算其相对位置放到压缩流中。

代码如下

/// <summary>
        /// 压缩文件或者文件夹
        /// </summary>
        /// <param name="_depositpath">压缩后文件的存放路径   如c:\\windows\abc.zip</param>
        /// <returns></returns>
        public bool compressionzip(string _depositpath)
        {
            bool result = true;
            filestream fs = null;
            try
            {
                zipoutputstream comstream = new zipoutputstream(file.create(_depositpath));
                comstream.setlevel(9);      //压缩等级
                foreach (string path in absolutepaths)
                {
                    //如果是目录
                    if (directory.exists(path))
                    {
                        zipfloder(path, comstream, path);
                    }
                    else if (file.exists(path))//如果是文件
                    {
                         fs = file.openread(path);
                        byte[] bts = new byte[fs.length];
                        fs.read(bts, 0, bts.length);
                        zipentry ze = new zipentry(new fileinfo(path).name);
                        comstream.putnextentry(ze);             //为压缩文件流提供一个容器
                        comstream.write(bts, 0, bts.length);  //写入字节
                    }
                }
                comstream.finish(); // 结束压缩
                comstream.close();
            }
            catch (exception ex)
            {
                if (fs != null)
                {
                    fs.close();
                }
                errormsg = ex.message;
                result = false;
            }
            return result;
        }
        //压缩文件夹
        private void zipfloder(string _ofloderpath, zipoutputstream zos, string _floderpath)
        {
            foreach (filesysteminfo item in new directoryinfo(_floderpath).getfilesysteminfos())
            {
                if (directory.exists(item.fullname))
                {
                    zipfloder(_ofloderpath, zos, item.fullname);
                }
                else if (file.exists(item.fullname))//如果是文件
                {
                    directoryinfo odir = new directoryinfo(_ofloderpath);
                    string fullname2 = new fileinfo(item.fullname).fullname;
                    string path = odir.name + fullname2.substring(odir.fullname.length, fullname2.length - odir.fullname.length);//获取相对目录
                    filestream fs = file.openread(fullname2);
                    byte[] bts = new byte[fs.length];
                    fs.read(bts, 0, bts.length);
                    zipentry ze = new zipentry(path);
                    zos.putnextentry(ze);             //为压缩文件流提供一个容器
                    zos.write(bts, 0, bts.length);  //写入字节
                }
            }
        }

关于解压  解压就简单多了。有文件解压文件，有文件夹 遍历，解压其中的文件。解压的文件中已经包含了其与文件夹的层次关系。

/// <summary>
        /// 解压
        /// </summary>
        /// <param name="_depositpath">压缩文件路径</param>
        /// <param name="_floderpath">解压的路径</param>
        /// <returns></returns>
        public bool decompressionzip(string _depositpath, string _floderpath)
        {
            bool result = true;
            filestream fs=null;
            try
            {
                zipinputstream inpstream = new zipinputstream(file.openread(_depositpath));
                zipentry ze = inpstream.getnextentry();//获取压缩文件中的每一个文件
                directory.createdirectory(_floderpath);//创建解压文件夹
                while (ze != null)//如果解压完ze则是null
                {
                    if (ze.isfile)//压缩zipinputstream里面存的都是文件。带文件夹的文件名字是文件夹\\文件名
                    {
                        string[] strs=ze.name.split('\\');//如果文件名中包含'\\‘则表明有文件夹
                        if (strs.length > 1)
                        {
                            //两层循环用于一层一层创建文件夹
                            for (int i = 0; i < strs.length-1; i++)
                            {
                                string floderpath=_floderpath;
                                for (int j = 0; j < i; j++)
                                {
                                    floderpath = floderpath + "\\" + strs[j];
                                }
                                floderpath=floderpath+"\\"+strs[i];
                                directory.createdirectory(floderpath);
                            }
                        }
                         fs = new filestream(_floderpath+"\\"+ze.name, filemode.openorcreate, fileaccess.write);//创建文件
                        //循环读取文件到文件流中
                        while (true)
                        {
                            byte[] bts = new byte[1024];
                           int i= inpstream.read(bts, 0, bts.length);
                           if (i > 0)
                           {
                               fs.write(bts, 0, i);
                           }
                           else
                           {
                               fs.flush();
                               fs.close();
                               break;
                           }
                        }
                    }
                    ze = inpstream.getnextentry();
                }
            }
            catch (exception ex)
            {
                if (fs != null)
                {
                    fs.close();
                }
                errormsg = ex.message;
                result = false;
            }
            return result;
        }

最后做个总结。c#作为高级语言，其强大的类库和第三方提供的类库。可以做很多事情。但也有弊端，用第三方类库性能不是很高。我压缩几百m的东西。cpu瞬间跑到50%多。比360压缩和zip压缩性能差远了。所以此类也就适用压缩比较小的东西。

完整例子下载地址