asp.net文件下载
这个是比较好用的下载文件的代码,可以下载大文件,资源占用小,可以限速,但是如果限速了就容易死机(在线的人多时),取之于网络
/// <summary>
/// 输出硬盘文件,提供下载 支持大文件、续传、速度限制、资源占用小
/// </summary>
/// <param name="Request">Page.Request对象</param>
/// <param name="Response">Page.Response对象</param>
/// <param name="fileName">下载文件名</param>
/// <param name="fullPath">带文件名下载路径</param>
/// <param name="speed">每秒允许下载的字节数</param>
/// <returns>返回是否成功</returns>
public bool ResponseFile(HttpRequest Request, HttpResponse Response, string fileName, string fullPath, long speed)
{
try
{
FileStream myFile = new FileStream(fullPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
BinaryReader br = new BinaryReader(myFile);
try
{
Response.AddHeader("Accept-Ranges", "bytes");
Response.Buffer = false;
long fileLength = myFile.Length;
long startBytes = 0;
int pack = 1024; //1K bytes
//int sleep = 200; //每秒5次 即5*10K bytes每秒
int sleep = (int)Math.Floor((decimal)1000 * pack / speed) + 1;
if (Request.Headers["Range"] != null)
{
Response.StatusCode = 206;
string[] range = Request.Headers["Range"].Split(new char[] { '=', '-' });
startBytes = Convert.ToInt64(range[1]);
}
Response.AddHeader("Content-Length", (fileLength - startBytes).ToString());
if (startBytes != 0)
{
Response.AddHeader("Content-Range", string.Format(" bytes {0}-{1}/{2}", startBytes, fileLength - 1, fileLength));
}
Response.AddHeader("Connection", "Keep-Alive");
Response.ContentType = "application/octet-stream";
Response.AddHeader("Content-Disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(fileName));
br.BaseStream.Seek(startBytes, SeekOrigin.Begin);
int maxCount = (int)Math.Floor((decimal)(fileLength - startBytes) / pack) + 1;
for (int i = 0; i < maxCount; i++)
{
if (Response.IsClientConnected)
{
Response.BinaryWrite(br.ReadBytes(pack));
//Thread.Sleep(sleep);//有问题,容易导致死机状态,只有设置了这里才可以限速,但在线人多时容易死机
}
else
{
i = maxCount;
}
}
}
catch
{
return false;
}
finally
{
br.Close();
myFile.Close();
}
}
catch
{
return false;
}
return true;
}
/// 输出硬盘文件,提供下载 支持大文件、续传、速度限制、资源占用小
/// </summary>
/// <param name="Request">Page.Request对象</param>
/// <param name="Response">Page.Response对象</param>
/// <param name="fileName">下载文件名</param>
/// <param name="fullPath">带文件名下载路径</param>
/// <param name="speed">每秒允许下载的字节数</param>
/// <returns>返回是否成功</returns>
public bool ResponseFile(HttpRequest Request, HttpResponse Response, string fileName, string fullPath, long speed)
{
try
{
FileStream myFile = new FileStream(fullPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
BinaryReader br = new BinaryReader(myFile);
try
{
Response.AddHeader("Accept-Ranges", "bytes");
Response.Buffer = false;
long fileLength = myFile.Length;
long startBytes = 0;
int pack = 1024; //1K bytes
//int sleep = 200; //每秒5次 即5*10K bytes每秒
int sleep = (int)Math.Floor((decimal)1000 * pack / speed) + 1;
if (Request.Headers["Range"] != null)
{
Response.StatusCode = 206;
string[] range = Request.Headers["Range"].Split(new char[] { '=', '-' });
startBytes = Convert.ToInt64(range[1]);
}
Response.AddHeader("Content-Length", (fileLength - startBytes).ToString());
if (startBytes != 0)
{
Response.AddHeader("Content-Range", string.Format(" bytes {0}-{1}/{2}", startBytes, fileLength - 1, fileLength));
}
Response.AddHeader("Connection", "Keep-Alive");
Response.ContentType = "application/octet-stream";
Response.AddHeader("Content-Disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(fileName));
br.BaseStream.Seek(startBytes, SeekOrigin.Begin);
int maxCount = (int)Math.Floor((decimal)(fileLength - startBytes) / pack) + 1;
for (int i = 0; i < maxCount; i++)
{
if (Response.IsClientConnected)
{
Response.BinaryWrite(br.ReadBytes(pack));
//Thread.Sleep(sleep);//有问题,容易导致死机状态,只有设置了这里才可以限速,但在线人多时容易死机
}
else
{
i = maxCount;
}
}
}
catch
{
return false;
}
finally
{
br.Close();
myFile.Close();
}
}
catch
{
return false;
}
return true;
}