下载文件夹里面的所有文件，并压缩成.zip压缩包的形式

http://www.aspsnippets.com/Articles/Download-multiple-files-as-Zip-Archive-File-in-ASPNet-using-C-and-VBNet.aspx

1.HTML tag

 <div>
        <asp:Button ID="Button1" runat="server" Text="DownLoadFile" OnClick="Button1_Click" />
    </div>

2.添加命名空间

using System.IO;
using Ionic.Zip;
using System.Collections.Generic;

3.下载文件事件

     protected void Button1_Click(object sender, EventArgs e)
        {
            string strPath = @"D:\ASP.NET_Products\2014.10Demos\Demos\FormsAuthentication\img";
            string[] files = System.IO.Directory.GetFiles(strPath);
            using (Ionic.Zip.ZipFile zip = new Ionic.Zip.ZipFile())
            {
                zip.AlternateEncodingUsage = ZipOption.AsNecessary;
                zip.AddDirectoryByName("Files");
                foreach (string fiel in files)
                {
                    strPath = System.IO.Path.Combine(strPath, fiel);
                    zip.AddFile(strPath, "Files");
                }
                Response.Clear();
                Response.BufferOutput = false;
                string zipName = String.Format("Zip_{0}.zip", DateTime.Now.ToString("yyyy-MMM-dd-HHmmss"));
                Response.ContentType = "application/zip";
                Response.AddHeader("content-disposition", "attachment; filename=" + zipName);
                zip.Save(Response.OutputStream);
                Response.End();
            }

            //下载一个文件的方法

            //Response.ContentType = ContentType;
            //Response.AppendHeader("Content-Disposition", "attachment; filename=" + Path.GetFileName(strPath));
            //Response.WriteFile(strPath);
            //Response.End();
        }

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使用 ZipFile.CreateFromDirectory方法快速创建ZIP文件

1. 引入命名空间

using System.IO.Compression;
using System.IO.Compression.ZipFile;

2. 调用方法

 ZipFile.CreateFromDirectory(@"C:\Users\v-xsong\Desktop\11", @"C:\Users\v-xsong\Desktop\11.zip",CompressionLevel.Fastest,true);
            Response.Write("OK");