Question

OK, I am most likely just missing something basic but I am super frustrated by this.

  public partial class myClass: System.Web.UI.Page
    { 
      public String pageHtml{
        get
        {
            if (ViewState["pageHtml"] != null)
            {
                return (string)ViewState["pageHtml"];
            }
            else
            {
                return null;
            }
        }
        set
        {
            ViewState["pageHtml"] = value;
        }
    }
      protected override void Render(HtmlTextWriter writer)
        {
            StringBuilder sbOut = new StringBuilder();
            StringWriter swOut = new StringWriter(sbOut);
            HtmlTextWriter htwOut = new HtmlTextWriter(swOut);
            base.Render(htwOut);
            string sOut = sbOut.ToString();
            pageHtml = sOut;
            writer.Write(sOut);

        }
      protected void btnDownloadPage_Click(object sender, EventArgs e)
        {

            DownloadTextAsFile("test", pageHtml, "aspx");

        }

        public void DownloadTextAsFile(string filename, string content, string extention)
        {


            string downloadFileName = filename + "." + extention;

            Response.AddHeader("Content-disposition", "attachment; filename=" + downloadFileName);
            Response.ContentType = "application/octet-stream";
            Response.Write(content);
            Response.End();
        }

}

when the DownloadPage button is clicked pageHtml is always null. What gives? I have tried moving the “pageHtml = sOut;” To after the “writer.Write(sOut);” And I have tried making pageHtml not persist to the viewstate but no such luck. (also I am aware my pageHtml get is not really checking anything as it returns null if ViewState[“pageHtml”] is null and I could just return ViewState[“pageHtml”] without the if-else check but I don’t care about that right now)

Answer 1

I think the ViewState doesn’t survive after a postback (your button click).
Try using session state instead.