网页编程中文件的上传

 文件上传的代码：

 protected void Page_Load(object sender, EventArgs e)
    {
        //HttpFileCollection files = HttpContext.Current.Request.Files;
        ////状态信息
        //System.Text.StringBuilder strMsg = new System.Text.StringBuilder();
        //for (int ifile = 0; ifile < files.Count; ifile++)
        //{
        //    HttpPostedFile postedfile = files[ifile];
        //    string filename, fileExt;
        //    filename = System.IO.Path.GetFileName(postedfile.FileName);    //获取文件名
        //    fileExt = System.IO.Path.GetExtension(filename);    //获取文件后缀

        //    int MaxAllowUploadFileSize = Convert.ToInt32(System.Configuration.ConfigurationManager.AppSettings["MaxAllowUploadFileSize"]);     //定义允许上传文件大小
        //    if (MaxAllowUploadFileSize == 0) { MaxAllowUploadFileSize = 26500; }
        //    string allowexts = System.Configuration.ConfigurationManager.AppSettings["AllowUploadFileType"];
        //    //定义允许上传文件类型
        //    if (allowexts == "") { allowexts = "doc|docx|rar|xls|xlsx|txt"; }
        //    Regex allowext = new Regex(allowexts);

        //    if (postedfile.ContentLength < MaxAllowUploadFileSize && allowext.IsMatch(fileExt)) //检查文件大小及扩展名
        //    {
        //        postedfile.SaveAs(Server.MapPath("upload\\" + filename + fileExt));    //upload为与本页面同一目录，可自行修改
        //    }
        //    else
        //    {
        //        Response.Write("<script>alert('不允许上传类型" + fileExt + "或文件过大')</script>");
        //    }
        //}

 

  protected void btupload_Click(object sender, EventArgs e)
    {
        bool fileIsValid = false;
        if (this.FileUpload1.HasFile)
        {
            String fileExtension = System.IO.Path.GetExtension(this.FileUpload1.FileName).ToLower();//获取文件扩展名
            String[] restricExtension = { ".xls", ".doc", ".txt" }; //限制上传类型
            for (int i = 0; i < restricExtension.Length; i++)
            {
                if (fileExtension == restricExtension[i])
                { fileIsValid = true; }
            }
            if (fileIsValid == true && this.FileUpload1.PostedFile.ContentLength <= 1e20)
            {
                try
                {
                    this.imgDisplay.ImageUrl = "~/WebSite1/" + FileUpload1.FileName;
                    this.FileUpload1.SaveAs(Server.MapPath("~/upfiles/") + FileUpload1.FileName);
                    this.Label1.Text = "文件上传成功";
                    this.Label1.Text += "<Br/>";
                    this.Label1.Text += "<li>" + "原文件路径:" + this.FileUpload1.PostedFile.FileName;
                    this.Label1.Text += "<Br/>";
                    this.Label1.Text += "<li>" + "文件大小:" + this.FileUpload1.PostedFile.ContentLength + "字节";
                    this.Label1.Text += "<Br/>";
                    this.Label1.Text += "<li>" + "文件类型:" + this.FileUpload1.PostedFile.ContentType;
                }
                catch
                {
                    this.Label1.Text = "文件上传不成功!";
                }
                finally { }
            }
            else
            {
                this.Label1.Text = "只能上传后缀为.xls,.doc,.txt的文件";
            }
        }

    }