1、首先读取文件夹下的文件，可能同时存在多个文件
2、选中文件，然后点击下载，同时可以选择多个文件。
思路：通过生产压缩包的形式进行下载，然后再清楚压缩包，这样用户可以一次性全部下载下来。
一、获取目录下的所有文件，然后绑定到checkboxlist中 ，代码如下：
ckl_ck.Items.Clear(); DirectoryInfo TheFolder = new DirectoryInfo(Server.MapPath("Resource/Help")); //遍历文件夹下的文件 foreach (FileInfo NextFile in TheFolder.GetFiles()) this.ckl_ck.Items.Add(NextFile.Name);
二、选中文件后，点击下载按钮。代码：
protected void Btn_down_Click(object sender, EventArgs e) { if (ckl_ck.Items.Count > 0) { List<string> listFJ = new List<string>();//保存附件路径 List<string> listFJName = new List<string>();//保存附件名字 for (int i = 0; i < ckl_ck.Items.Count; i++) { if (ckl_ck.Items[i].Selected) { listFJ.Add(Server.MapPath("Resource/Help/") + ckl_ck.Items[i].Text); listFJName.Add(ckl_ck.Items[i].Text); } } string time = DateTime.Now.Ticks.ToString(); ZipFileMain(listFJ.ToArray(), listFJName.ToArray(), Server.MapPath("Resource/Help/" + time + ".zip"), 9);//压缩文件 DownloadFile(Server.UrlEncode("附件.zip"), Server.MapPath("Resource/Help/" + time + ".zip"));//下载文件 } } private void DownloadFile(string fileName, string filePath) { FileInfo fileInfo = new FileInfo(filePath); Response.Clear(); Response.ClearContent(); Response.ClearHeaders(); Response.AddHeader("Content-Disposition", "attachment;filename=" + fileName); Response.AddHeader("Content-Length", fileInfo.Length.ToString()); Response.AddHeader("Content-Transfer-Encoding", "binary"); Response.ContentType = "application/octet-stream"; Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312"); Response.WriteFile(fileInfo.FullName); Response.Flush(); File.Delete(filePath);//删除已下载文件 Response.End(); } /// <summary> /// 压缩文件 /// </summary> /// <param>要压缩的所有文件（完全路径)</param> /// <param>文件名称</param> /// <param>压缩后文件路径</param> /// <param>压缩级别</param> public void ZipFileMain(string[] filenames, string[] fileName, string name, int Level) { ZipOutputStream s = new ZipOutputStream(File.Create(name)); Crc32 crc = new Crc32(); //压缩级别 s.SetLevel(Level); // 0 - store only to 9 - means best compression try { int m = 0; foreach (string file in filenames) { //打开压缩文件 FileStream fs = File.OpenRead(file);//文件地址 byte[] buffer = new byte[fs.Length]; fs.Read(buffer, 0, buffer.Length); //建立压缩实体 ZipEntry entry = new ZipEntry(fileName[m].ToString());//原文件名 //时间 entry.DateTime = DateTime.Now; //空间大小 entry.Size = fs.Length; fs.Close(); crc.Reset(); crc.Update(buffer); entry.Crc = crc.Value; s.PutNextEntry(entry); s.Write(buffer, 0, buffer.Length); m++; } } catch { throw; } finally { s.Finish(); s.Close(); } }
三、系统中需要引用的dll 需要下载。
四、运行效果如图：
