文件下載與ZIP打包和解壓縮

前段時間在文件下載時遇到點問題, 後來發現網絡上對ZIP包的論題很多, 特將經驗分享下.
文件下載:

  private void DownLoadFileByPath(string strFileFullPath)
    {
        string strFileName = strFileFullPath.Substring(strFileFullPath.LastIndexOf("\\") + 1);
        int dot = strFileName.LastIndexOf(".");
        string strFileType = string.Empty;
        string strContentType = string.Empty;
        if (dot != -1 && strFileName.Length > dot + 1)
        {
            strFileType = strFileName.Substring(dot + 1).ToUpper();
        }

        if (strFileType.ToUpper() == "PDF")
        {
            strContentType = "application/pdf";
        }
        else if (strFileType.ToUpper() == "TIF")
        {
            strContentType = "image/tiff";
        }
        else if (strFileType.ToUpper() == "DOC")
        {
            strContentType = "application/msword";
        }
        else if (strFileType.ToUpper() == "xls")
        {
            strContentType = "application/vnd.ms-excel";
        }

        Response.Clear();
        Response.ContentType = strContentType;
        Response.BufferOutput = false;
        Response.AppendHeader("content-disposition", "attachment;filename=" + strFileName);
        Response.WriteFile(strFileFullPath);
        Response.Flush();
        System.IO.File.Delete(strFileFullPath);
        Response.Close();
    }

對於多個文件同時下載, 一般通過先打包成一個文件,到客戶端再解壓縮的方式實現.
打包操作:

 1  public static void ZipDir(string pFoldToZip, string pZipedFileFullName)
 2    {
 3        string sOldCurDir = Directory.GetCurrentDirectory();
 4        string sCurDir = pFoldToZip;//.Substring(0,pFoldToZip.LastIndexOf("\\"));
 5        if (!Directory.Exists(sCurDir))
 6            Directory.CreateDirectory(sCurDir);
 7        Directory.SetCurrentDirectory(sCurDir);
 8        string sCurZipFold = pFoldToZip;
 9        string[] filenames = Directory.GetFiles(sCurZipFold);//Directory.GetFiles(args[0]);
10        string[] filefolds = Directory.GetDirectories(sCurZipFold);//Directory.GetFiles(args[0]);
11
12
13        Crc32 crc = new Crc32();
14        ZipOutputStream s = new ZipOutputStream(File.Create(pZipedFileFullName)); //File.Create(args[1]));        
15        s.SetLevel(6); // 0 - store only to 9 - means best compression
16        while (true)
17        {
18            if ((filenames == null || filenames.Length <= 0) && (filefolds == null || filefolds.Length <= 0)) break;
19            foreach (string file in filenames)
20            {
21                if (file.Trim() == "") continue;
22                //string sFileXiangDui = file.Replace(sCurDir,".");
23                string sFileXiangDui = file.Replace(sCurDir + "\\", "");
24                FileStream fs = File.OpenRead(sFileXiangDui);
25
26                byte[] buffer = new byte[fs.Length];
27                fs.Read(buffer, 0, buffer.Length);
28                ZipEntry entry = new ZipEntry(sFileXiangDui);
29
30                entry.DateTime = DateTime.Now;
31
32                // set Size and the crc, because the information
33                // about the size and crc should be stored in the header
34                // if it is not set it is automatically written in the footer.
35                // (in this case size == crc == -1 in the header)
36                // Some ZIP programs have problems with zip files that don't store
37                // the size and crc in the header.
38                entry.Size = fs.Length;
39                fs.Close();
40
41                crc.Reset();
42                crc.Update(buffer);
43
44                entry.Crc = crc.Value;
45
46                s.PutNextEntry(entry);
47
48                s.Write(buffer, 0, buffer.Length);
49
50            }
51
52            if (filefolds != null && filefolds.Length > 0)
53            {
54                //filenames = GetFiles(filefolds);
55                //filefolds = GetSubFolds(filefolds);
56            }
57            else
58            {
59                filenames = null;
60                filefolds = null;
61            }
62        }
63        s.Finish();
64        s.Close();
65        Directory.SetCurrentDirectory(sOldCurDir);
66    }
67

解壓縮操作:

 1  public static void UnZip(string pCurDir, string pZipedFileName)
 2    {
 3        if (!Directory.Exists(pCurDir))
 4        {
 5            Directory.CreateDirectory(pCurDir);
 6        }
 7
 8        string strOriCurrentDir = Directory.GetCurrentDirectory();
 9        Directory.SetCurrentDirectory(pCurDir);
10        ZipInputStream s = new ZipInputStream(File.OpenRead(pZipedFileName));
11
12        ZipEntry theEntry;
13        while ((theEntry = s.GetNextEntry()) != null)
14        {
15
16            Console.WriteLine(theEntry.Name);
17
18            string directoryName = Path.GetDirectoryName(theEntry.Name);
19            string fileName = Path.GetFileName(theEntry.Name);
20
21            // create directory
22            if (directoryName.Trim() != "" && !Directory.Exists(directoryName))
23                Directory.CreateDirectory(directoryName);
24
25            if (fileName != String.Empty)
26            {
27                FileStream streamWriter = File.Create(theEntry.Name);
28
29                int size = 2048;
30                byte[] data = new byte[2048];
31                while (true)
32                {
33                    size = s.Read(data, 0, data.Length);
34                    if (size > 0)
35                    {
36                        streamWriter.Write(data, 0, size);
37                    }
38                    else
39                    {
40                        break;
41                    }
42                }
43
44                streamWriter.Close();
45            }
46        }
47        s.Close();
48
49        Directory.SetCurrentDirectory(strOriCurrentDir);
50    }

這裡使用到組件ICSharpCode.SharpZipLib.
http://www.icsharpcode.net/OpenSource/SharpZipLib/Default.aspx
感謝ZCC在文件下載過程中對我的指導.