asp.net 实现简单的文件上传和下载

Question

文件上传，并存入数据库，然后显示，单击显示的结果则下载指定的文件。
比如上传了一个文件 aaa ，然后在显示的结果中单击 aaa 则实现下载 文件aaa的功能。
鄙人是新手，所以请尽量写的简单一点

Answer 1

FileInfo Fi = new FileInfo(filePath);
if (Fi.Exists)
{
  FileStream fs = new FileStream(filePath, FileMode.Open);
  byte[] bytes = new byte[(int)fs.Length];
  fs.Read(bytes, 0, bytes.Length);
  fs.Close();
  Response.ContentType = "application/octet-stream";
  Response.AddHeader("Content-Disposition", "attachment; filename=1.excel");
  Response.BinaryWrite(bytes);
  Response.Flush();
  Response.End();
}
string path = Server.MapPath("~/") + "";
Response.AppendHeader("Content-Disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(obj.Name, System.Text.Encoding.GetEncoding("utf-8")));
Response.ContentType = "application/octet-stream";
Response.WriteFile("" + path + "");
Response.End();
if (fileUpload.HasFile)  
  {  
  string savePath = Server.MapPath("~/upload/");  
  if(!System.IO.Directory.Exists(savePath))  
  {  
  System.IO.Directory.CreateDirectory(savePath);  
  }  
  savePath = savePath + "\\" + fileUpload.FileName;  
  fileUpload.SaveAs(savePath);  
  }  
 
 

Answer 2

参考：
http://topic.csdn.net/u/20090819/15/cf431ac6-3bb9-4e22-9974-8ef4b7269d28.html

Answer 3

 您的回复正文中有非法词或词组！http://download.csdn.net/source/933390

Answer 4

fileUpload.SaveAs(savePath);//上传
Response.ContentType = "application/octet-stream";
                Response.AddHeader("Content-Disposition", "attachment;filename=" + 文件名称);
                response.WriteFile(Filepath);//下载   

Answer 5

  把地址存在数据库里面。。下载直接格URL地址

Answer 6

参考：
http://topic.csdn.net/u/20090819/15/cf431ac6-3bb9-4e22-9974-8ef4b7269d28.html
就是拉几个控件写点烂代码,然后就O了.

Answer 7

--这是Js,验证格式(我这是'xls'，‘xlsx'）格式的)<script type="text/javascript">
    function checkFileExtension(elem) {
        var filePath = elem.value;        if(filePath.indexOf('.') == -1)
            return false;
        
        var validExtensions = new Array();
        var ext = filePath.substring(filePath.lastIndexOf('.') + 1).toLowerCase();   
      
        validExtensions[0] = 'xls';
        validExtensions[1] = 'xlsx';
    
        for(var i = 0; i < validExtensions.length; i++) {
            if(ext == validExtensions[i])
                return true;
        }
        alert('后缀为:( ' + ext.toUpperCase() + ')的文件格式 无法导入!');
        return false;
    }
    </script>--后台  /// <summary>
    /// 上传
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    protected void btnSubmit_Click(object sender, EventArgs e)
    {
        if (FileUpload1.HasFile)
        {
            
            string loadPath =Server.MapPath("../")+ ConfigurationSettings.AppSettings["ExcelFolder"];
            string fileName = Server.HtmlEncode(FileUpload1.FileName);
            if (!System.IO.Directory.Exists(loadPath))
            {
                System.IO.Directory.CreateDirectory(loadPath);
            }
            string Extension = System.IO.Path.GetExtension(FileUpload1.PostedFile.FileName);
            if (".xls.xlsx".ToUpper().IndexOf(Extension.ToUpper()) < 0)
            {
                DisplayAlert("文件格式不正确！请选择(.xls.xlsx)格式的文件上传！");
                return;
            }            Import_CounteractBLL bll = new Import_CounteractBLL();
           
            string filepath=loadPath + string.Format("{0}{1}", Guid.NewGuid().ToString(), Extension);            try
            {
                if (System.IO.File.Exists(filepath))
                {
                    System.IO.File.Delete(filepath);
                }                FileUpload1.SaveAs(filepath);
                DataTable dt = bll.LoadUpByExcel(filepath);//bll.LoadExcelData(0, path, 2, 1);
                List<string> list = new List<string>();
                foreach (DataRow dr in dt.Rows)
                {
                    if (list.Contains(string.Format("{0}", dr["OperationCode"]).Trim())) continue;
                    list.Add(string.Format("{0}", dr["OperationCode"]).Trim());
                }
                bool flag = bll.Counteract_Exsit(DateTime.Now, fileName,list.ToArray());
                if (flag)
                {
                    DisplayAlert("当天的数据已经存在!重新导入需先删除当天的数据！");
                    return;
                }                bll.ImportData(string.Format("{0}", Session["userid"]), fileName, dt);
                DisplayAlert(fileName + ":上传成功!");                //OutputDataGrid1.SortCondition = " Creatertime desc";
                //OutputDataGrid1.Update();
                Response.Redirect("CounteractManage.aspx");
            }
            catch (Exception xe)
            {
                DisplayAlert(xe.Message);
            }
            finally {
                System.IO.Directory.Delete(loadPath, true);
            }
        }
        else
        {
            DisplayAlert("请选择需要上传的文件!");
        }
    }//下载protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
    {
        if (e.CommandName == "DK")
        {
            string fileName = e.CommandArgument.ToString();
            string filePath = TxtExport + "\\" + fileName;
            if (File.Exists(filePath))
            {
                FileInfo file = new FileInfo(filePath);
                Response.ContentEncoding = System.Text.Encoding.GetEncoding("UTF-8"); //解决中文乱码
                Response.AddHeader("Content-Disposition", "attachment; filename=" + Server.UrlEncode(file.Name)); //解决中文文件名乱码    
                Response.AddHeader("Content-length", file.Length.ToString());
                Response.ContentType = "appliction/octet-stream";
                Response.WriteFile(file.FullName);
                Response.End();
            }
        }
    }