asp.net下载文件 - accphy的专栏 - CSDNBlog

来源：互联网发布：怎么求根号的值 java 编辑：程序博客网时间：2024/05/14 18:31

//调用下载文件的方法
Session["file_txt"] = Request.QueryString["file_name"].ToString();//文件名字
            string file_name = Session["file_txt"].ToString();//文件名字
            bool success = ResponseFile(Page.Request, Page.Response, file_name, Request.MapPath("../newadmin/upfiles/file_xz/" + file_name), 1024000);
      if(!success)

Response.Write("下载文件出错！");

Page.Response.End();
}
///

/// _fileName: 下载文件名， _fullPath: 带文件名下载路径， _speed 每秒允许下载的字节数返回是否成功
///

    /// Page.Request对象
    /// Page.Response对象
    /// 下载文件名
    /// 带文件名下载路径
    ///
    ///
    public static 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 = 10240; //10K bytes
                //int sleep = 200;   //每秒5次   即5*10K bytes每秒
                int sleep = (int)(1000 * pack / _speed) + 1;
                //int sleep =(int)System.Math.Floor(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=" + HttpUtility.UrlEncode(_fileName, System.Text.Encoding.UTF8));
                br.BaseStream.Seek(startBytes, SeekOrigin.Begin);
                int maxCount = (int)((fileLength - startBytes) / pack) + 1;
                //int maxCount =(int)System.Math.Floor((fileLength - startBytes) / pack) + 1;
                for (int i = 0; i < maxCount; i++)
                {
                    if (_Response.IsClientConnected)
                    {
                        _Response.BinaryWrite(br.ReadBytes(pack));
                        Thread.Sleep(sleep);
                    }
                    else
                    {
                        i = maxCount;
                    }
                }
            }
            catch
            {
                return false;
            }
            finally
            {
                br.Close();
                myFile.Close();
            }
        }
        catch(Exception ex)
        {
            throw (ex);
        }