ASP.NET批量下载文件的方法

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

复制代码代码如下:

//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

复制代码代码如下:

/// <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

复制代码代码如下:

/// <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", "attachment;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

复制代码代码如下:

/// <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;
    }
}

DEMO下载地址：https://dwz.cn/Jw3z6fVq