asp.net实现文件夹及文件压缩，并实现下载(三)——文件超过150M

来源：互联网发布：软件测试压力测试编辑：程序博客网时间：2024/06/07 00:16

asp.net实现文件夹及文件压缩，并实现下载(三)——文件超过150M

添加引用：ICSharpCode.SharpZipLib.dll

代码：
protected void Button1_Click(object sender, EventArgs e)
{
string filePath = Server.MapPath("files");
string strFileName = HttpUtility.UrlEncode("files").Replace('+', ' ');
string fileName = "files.zip";//客户端保存的文件名
string Path = Server.MapPath(fileName);//路径
System.IO.FileStream iStream = null;
try
{
zos = new ZipOutputStream(File.Create(filePath + ".zip"));//创建压缩文件，保存的服务器中
strBaseDir = filePath + "\\";
addZipEntry(strBaseDir);//压缩文件
zos.Finish();
zos.Close();
//分块下载文件
iStream = System.IO.File.OpenRead(Path);
System.IO.FileInfo fileInfo = new System.IO.FileInfo(Path);
if (fileInfo.Exists == true)
{
const long ChunkSize = 1048576;//1M 每次读取文件，只读取1M，这样可以缓解服务器的压力
byte[] buffer = new byte[ChunkSize];
Response.Clear();
long dataLengthToRead = iStream.Length;//获取下载的文件总大小
Response.ContentType = "application/octet-stream";
Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName));
while (dataLengthToRead > 0 && Response.IsClientConnected)
{
int lengthRead = iStream.Read(buffer, 0, Convert.ToInt32(ChunkSize));//读取的大小
Response.OutputStream.Write(buffer, 0, lengthRead);
Response.Flush();
dataLengthToRead = dataLengthToRead - lengthRead;
}
Response.Close();
}
zos.Close();
iStream.Close();
Response.End();
Response.Clear();
Response.End();
}
catch (Exception ex)
{
if (iStream != null)
iStream.Close();
////zos.Close();
ScriptManager.RegisterStartupScript(this, GetType(), "alert", "<script>alert('下载有问题！');</script>", false);
}
}

private void addZipEntry(string path)
{
Crc32 crc = new Crc32();
DirectoryInfo di = new DirectoryInfo(path);
FileStream fs = null;
try
{
foreach (DirectoryInfo item in di.GetDirectories())
{
addZipEntry(item.FullName);
}
foreach (FileInfo item in di.GetFiles())
{
fs = File.OpenRead(item.FullName);
if (fs.Length != 0)
{
long fileLength = fs.Length;
long pai = 1024 * 1024 * 20;//每M写一次
long forint = fs.Length / pai + 1;
byte[] buffer = null;
ZipEntry entry = null;
if (fileLength < 104857600)//150 * 1024 * 1024
{
buffer = new byte[fs.Length];
fs.Read(buffer, 0, buffer.Length);
string strEntryName = item.FullName.Replace(strBaseDir, "");
entry = new ZipEntry(strEntryName);
zos.PutNextEntry(entry);
zos.Write(buffer, 0, buffer.Length);
}
else
{
entry = new ZipEntry(item.FullName.Replace(strBaseDir, ""));
entry.Size = fs.Length;
entry.DateTime = DateTime.Now;
zos.PutNextEntry(entry);
for (long i = 1; i <= forint; i++)
{
if (pai * i < fs.Length)
{
buffer = new byte[pai];
fs.Seek(pai * (i - 1), System.IO.SeekOrigin.Begin);
}
else
{
if (fs.Length < pai)
{
buffer = new byte[fs.Length];
}
else
{
buffer = new byte[fs.Length - pai * (i - 1)];
fs.Seek(pai * (i - 1), System.IO.SeekOrigin.Begin);
}
}
fs.Read(buffer, 0, buffer.Length);
crc.Reset();
crc.Update(buffer);
zos.Write(buffer, 0, buffer.Length);
zos.Flush();
}
}
}
fs.Close();
}
}
catch (Exception ex)
{
if (fs != null)
fs.Close();
ScriptManager.RegisterStartupScript(this, GetType(), "alert", "<script>alert('压缩有问题！');</script>", false);
}
}

这个方法先是将生成的压缩包存放到服务器中，然后再下载