C# 文件压缩方法

using System;
using System.IO;
using System.IO.Packaging;

namespace Utility
{
    public class ZipHelper
    {
        ///<summary>
        /// Add a folder along with its subfolders to a Package
        /// </summary>
        /// <param name="folderName">The folder to add</param>
        /// <param name="compressedFileName">The package to create</param>
        /// <param name="overrideExisting">Override exsisitng files</param>
        /// <returns></returns>
        public static bool PackageFolder(string folderName, string compressedFileName, bool overrideExisting)
        {
            if (folderName.EndsWith(@"\"))
                folderName = folderName.Remove(folderName.Length - 1);
            bool result = false;
            if (!Directory.Exists(folderName))
            {
                return result;
            }

            if (!overrideExisting && File.Exists(compressedFileName))
            {
                return result;
            }
            try
            {
                using (Package package = Package.Open(compressedFileName, FileMode.Create))
                {
                    var fileList = Directory.EnumerateFiles(folderName, "*", SearchOption.AllDirectories);
                    foreach (string fileName in fileList)
                    {

                        //The path in the package is all of the subfolders after folderName
                        string pathInPackage;
                        pathInPackage = Path.GetDirectoryName(fileName).Replace(folderName, string.Empty) + "/" + Path.GetFileName(fileName);

                        Uri partUriDocument = PackUriHelper.CreatePartUri(new Uri(pathInPackage, UriKind.Relative));
                        PackagePart packagePartDocument = package.CreatePart(partUriDocument, "", CompressionOption.Maximum);
                        using (FileStream fileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read))
                        {
                            fileStream.CopyTo(packagePartDocument.GetStream());
                        }
                    }
                }
                result = true;
            }
            catch (Exception e)
            {
                throw new Exception("Error zipping folder " + folderName, e);
            }

            return result;
        }
    }
}

using ICSharpCode.SharpZipLib.Checksums;
using ICSharpCode.SharpZipLib.Zip;
using System;
using System.IO;

namespace Utility
{
    /// <summary>
    /// 需要引用NuGet包：ICSharpCode.SharpZipLib
    /// </summary>
    public class ZipNewHelper
    {
        public void ZipFile(string strFile, string strZip)
        {
            if (strFile[strFile.Length - 1] != Path.DirectorySeparatorChar)
                strFile += Path.DirectorySeparatorChar;
            ZipOutputStream s = new ZipOutputStream(File.Create(strZip));
            s.SetLevel(6); // 0 - store only to 9 - means best compression
            zip(strFile, s, strFile);
            s.Finish();
            s.Close();
        }


        private void zip(string strFile, ZipOutputStream s, string staticFile)
        {
            if (strFile[strFile.Length - 1] != Path.DirectorySeparatorChar) strFile += Path.DirectorySeparatorChar;
            Crc32 crc = new Crc32();
            string[] filenames = Directory.GetFileSystemEntries(strFile);
            foreach (string file in filenames)
            {

                if (Directory.Exists(file))
                {
                    zip(file, s, staticFile);
                }

                else // 否则直接压缩文件
                {
                    //打开压缩文件
                    FileStream fs = File.OpenRead(file);

                    byte[] buffer = new byte[fs.Length];
                    fs.Read(buffer, 0, buffer.Length);
                    string tempfile = file.Substring(staticFile.LastIndexOf("\\") + 1);
                    ZipEntry entry = new ZipEntry(tempfile);

                    entry.DateTime = DateTime.Now;
                    entry.Size = fs.Length;
                    fs.Close();
                    crc.Reset();
                    crc.Update(buffer);
                    entry.Crc = crc.Value;
                    s.PutNextEntry(entry);

                    s.Write(buffer, 0, buffer.Length);
                }
            }
        }
    }
}