SharpZipLib 是一个广泛使用的开源库，用于在 .NET 应用程序中处理压缩和解压缩文件。它支持多种压缩格式，包括 Zip、GZip、BZip2 和 TAR。本文将介绍如何在 C# 中使用 SharpZipLib 进行文件压缩和解压缩操作。

安装 SharpZipLib

首先，你需要在项目中安装 SharpZipLib 库。你可以使用 NuGet 包管理器来安装：

C#
Install-Package SharpZipLib

或者在 PackageManager 控制台中运行：

PowerShell
PM> Install-Package SharpZipLib

压缩文件为 ZIP 格式

简单的 ZIP 压缩

下面是一个简单的示例，展示如何将一个文件压缩成 ZIP 格式：

C#
using ICSharpCode.SharpZipLib.Zip;

namespace AppSharpZip
{
    internal class Program
    {
        static void Main(string[] args)
        {
            string sourceFile = @"d:\example.txt";
            string zipFile = @"d:\example.zip";

            using (FileStream fsOut = File.Create(zipFile))
            using (ZipOutputStream zipStream = new ZipOutputStream(fsOut))
            {
                zipStream.SetLevel(3); // 压缩级别 0-9

                byte[] buffer = new byte[4096];
                ZipEntry entry = new ZipEntry(Path.GetFileName(sourceFile));
                entry.DateTime = DateTime.Now;

                zipStream.PutNextEntry(entry);

                using (FileStream fsIn = File.OpenRead(sourceFile))
                {
                    int sourceBytes;
                    do
                    {
                        sourceBytes = fsIn.Read(buffer, 0, buffer.Length);
                        zipStream.Write(buffer, 0, sourceBytes);
                    } while (sourceBytes > 0);
                }

                zipStream.CloseEntry();
            }
            Console.WriteLine("压缩成功！");
        }
    }
}

压缩文件夹

下面是一个递归压缩整个文件夹的示例：

C#
using ICSharpCode.SharpZipLib.Zip;

namespace AppSharpZip
{
    internal class Program
    {
        public static void Main(string[] args)
        {
            string folderToZip = "D:\\sqlmodel";
            string zipFile = "D:\\sqlmodelfolder.zip";

            using (FileStream fsOut = File.Create(zipFile))
            using (ZipOutputStream zipStream = new ZipOutputStream(fsOut))
            {
                zipStream.SetLevel(3); // 压缩级别 0-9

                ZipDirectory(folderToZip, zipStream, folderToZip.Length + 1);
            }
            Console.WriteLine("文件夹压缩成功！");
        }

        private static void ZipDirectory(string folder, ZipOutputStream zipStream, int folderOffset)
        {
            string[] files = Directory.GetFiles(folder);

            foreach (string fileName in files)
            {
                FileInfo fi = new FileInfo(fileName);
                string entryName = fileName.Substring(folderOffset); // 截断绝对路径
                entryName = ZipEntry.CleanName(entryName); // Windows 和 Unix 路径处理

                ZipEntry newEntry = new ZipEntry(entryName);
                newEntry.DateTime = fi.LastWriteTime;
                newEntry.Size = fi.Length;

                zipStream.PutNextEntry(newEntry);

                byte[] buffer = new byte[4096];
                using (FileStream fsInput = fi.OpenRead())
                {
                    int sourceBytes;
                    do
                    {
                        sourceBytes = fsInput.Read(buffer, 0, buffer.Length);
                        zipStream.Write(buffer, 0, sourceBytes);
                    } while (sourceBytes > 0);
                }
                zipStream.CloseEntry();
            }

            string[] folders = Directory.GetDirectories(folder);
            foreach (string folderName in folders)
            {
                ZipDirectory(folderName, zipStream, folderOffset);
            }
        }
    }
}

解压 ZIP 文件

下面是一个解压 ZIP 文件的示例：

C#
using ICSharpCode.SharpZipLib.Zip;

namespace AppSharpZip
{
    internal class Program
    {
        public static void Main(string[] args)
        {
            string zipFile = "d:\\example.zip";
            string extractPath = "d:\\";

            using (ZipInputStream zipStream = new ZipInputStream(File.OpenRead(zipFile)))
            {
                ZipEntry entry;
                while ((entry = zipStream.GetNextEntry()) != null)
                {
                    string directoryName = Path.GetDirectoryName(entry.Name);
                    string fileName = Path.GetFileName(entry.Name);

                    if (!string.IsNullOrEmpty(directoryName))
                    {
                        Directory.CreateDirectory(Path.Combine(extractPath, directoryName));
                    }

                    if (!string.IsNullOrEmpty(fileName))
                    {
                        string filePath = Path.Combine(extractPath, entry.Name);
                        using (FileStream streamWriter = File.Create(filePath))
                        {
                            int size = 2048;
                            byte[] data = new byte[size];
                            while (true)
                            {
                                size = zipStream.Read(data, 0, data.Length);
                                if (size > 0)
                                {
                                    streamWriter.Write(data, 0, size);
                                }
                                else
                                {
                                    break;
                                }
                            }
                        }
                    }
                }
            }
            Console.WriteLine("解压成功！");
        }
    }
}

压缩为 GZip 格式

除了 ZIP 之外，SharpZipLib 还支持 GZip 格式。下面是一个将文件压缩为 GZip 的示例：

C#
using ICSharpCode.SharpZipLib.GZip;
using ICSharpCode.SharpZipLib.Zip;

namespace AppSharpZip
{
    internal class Program
    {
        public static void Main(string[] args)
        {
            string sourceFile = "d:\\example.txt";
            string gzipFile = "d:\\example.gz";

            using (FileStream fsOut = File.Create(gzipFile))
            using (GZipOutputStream gzipStream = new GZipOutputStream(fsOut))
            {
                byte[] buffer = new byte[4096];
                using (FileStream fsIn = File.OpenRead(sourceFile))
                {
                    int sourceBytes;
                    do
                    {
                        sourceBytes = fsIn.Read(buffer, 0, buffer.Length);
                        gzipStream.Write(buffer, 0, sourceBytes);
                    } while (sourceBytes > 0);
                }
            }
            Console.WriteLine("GZip 压缩成功！");
        }
    }
}

解压 GZip 文件

C#
using ICSharpCode.SharpZipLib.GZip;
using ICSharpCode.SharpZipLib.Zip;

namespace AppSharpZip
{
    internal class Program
    {
        public static void Main(string[] args)
        {
            string gzipFile = "d:\\example.gz";
            string decompressedFile = "d:\\example1.txt";

            using (FileStream fsIn = File.OpenRead(gzipFile))
            using (GZipInputStream gzipStream = new GZipInputStream(fsIn))
            using (FileStream fsOut = File.Create(decompressedFile))
            {
                byte[] buffer = new byte[4096];
                int bytesRead;
                while ((bytesRead = gzipStream.Read(buffer, 0, buffer.Length)) > 0)
                {
                    fsOut.Write(buffer, 0, bytesRead);
                }
            }
            Console.WriteLine("GZip 解压成功！");
        }
    }
}

总结

SharpZipLib 是一个功能强大的库，可以轻松地集成到您的 .NET 项目中处理压缩和解压缩任务。本文介绍了如何在 C# 项目中使用 SharpZipLib 进行文件和文件夹的压缩和解压缩操作，示例涵盖了 ZIP 和 GZip 两种常见的压缩格式。希望本文能帮助您更好地理解和应用 SharpZipLib。