ASP.NET批量下载文件

一、实现步骤

　　在用户操作界面，由用户选择需要下载的文件，系统根据所选文件，在服务器上创建用于存储所选文件的临时文件夹，将所选文件拷贝至临时文件夹。然后调用 RAR程序，对临时文件夹进行压缩，然后输出到客户端。最后删除临时文件夹。

二、代码实现

1、ASP.NET批量下载 核心代码

//遍历服务器指定文件夹下的所有文件
string path = "uploads/Image/";
string serverPath = Server.MapPath(path);

//创建临时文件夹
string tempName = DateTime.Now.ToString("yyyyMMddHHMMss");
string tempFolder = Path.Combine(serverPath, tempName);
Directory.CreateDirectory(tempFolder);

DirectoryInfo folder = new DirectoryInfo(serverPath);

foreach(FileInfo file in folder.GetFiles())
{
    string filename = file.Name;
    File.Copy(serverPath + "/" + filename, tempFolder + "/" + filename);
}
//ZKHelper.JSHelper.Alert("图片拷贝成功!");
//产生RAR文件，及文件输出
RARSave(tempFolder, tempName);
 DownloadRAR(tempFolder + "\\\\" + tempName + ".rar");

2、RARSave(string tempFolder, string tempName) 方法

        /// <summary>
        /// 生成RAR文件
        /// </summary>
        /// <param name="path">存放复制文件的目录</param>
        /// <param name="rarPatch">RAR文件存放目录</param>
        /// <param name="rarName">RAR文件名</param>
        private void RARSave(string rarPatch, string rarName)
        {
            string the_rar;
            RegistryKey the_Reg;
            Object the_Obj;
            string the_Info;
            ProcessStartInfo the_StartInfo;
            Process the_Process;
            try
            {
                the_Reg = Registry.ClassesRoot.OpenSubKey(@"WinRAR");
                the_Obj = the_Reg.GetValue("");
                the_rar = the_Obj.ToString();
                the_Reg.Close();
                the_rar = the_rar.Substring(1, the_rar.Length - 7);
                the_Info = " a " + rarName + " -r";
                the_StartInfo = new ProcessStartInfo();
                the_StartInfo.FileName = "WinRar";//the_rar;
                the_StartInfo.Arguments = the_Info;
                the_StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
                //打包文件存放目录
                the_StartInfo.WorkingDirectory = rarPatch;
                the_Process = new Process();
                the_Process.StartInfo = the_StartInfo;
                the_Process.Start();
                the_Process.WaitForExit();
                the_Process.Close();
            }
            catch (Exception)
            {
                throw;
            }
        }

3、DownloadRAR(string file)方法

        /// <summary>
        /// 下载生成的RAR文件
        /// </summary>
        private void DownloadRAR(string file)
        {
            FileInfo fileInfo = new FileInfo(file);
            Response.Clear();
            Response.ClearContent();
            Response.ClearHeaders();
            Response.AddHeader("Content-Disposition", "p_w_upload;filename=" + fileInfo.Name);
            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();
            string tempPath = file.Substring(0, file.LastIndexOf("\\\\"));
            //删除临时目录下的所有文件
            DeleteFiles(tempPath);
            //删除空目录
            Directory.Delete(tempPath);
            Response.End();
        }

4、DeleteFiles(string tempPath) 方法

        /// <summary>
        /// 删除临时目录下的所有文件
        /// </summary>
        /// <param name="tempPath">临时目录路径</param>
        private void DeleteFiles(string tempPath)
        {
            DirectoryInfo directory = new DirectoryInfo(tempPath);
            try
            {
                foreach (FileInfo file in directory.GetFiles())
                {
                    if (file.Attributes.ToString().IndexOf("ReadOnly") != -1)
                    {
                        file.Attributes = FileAttributes.Normal;
                    }
                    File.Delete(file.FullName);
                }
            }
            catch (Exception)
            {
                throw;
            }
        }