Insert view state data in Page render event (C#) : ViewState « Sessions « ASP.NET Tutorial






<%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    
    </div>
    </form>
</body>
</html>

File: Default.aspx.cs

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.IO;

public partial class _Default : System.Web.UI.Page 
{
    protected void Page_Load(object sender, EventArgs e)
    {
        ViewState["Example"] = "java2s.com";
    }

    protected override void Render(System.Web.UI.HtmlTextWriter writer)
    {
        System.IO.StringWriter stringWriter = new System.IO.StringWriter();
        HtmlTextWriter htmlWriter = new HtmlTextWriter(stringWriter);
        base.Render(htmlWriter);
        string html = stringWriter.ToString();
        int StartPoint = html.IndexOf("<input type=\"hidden\" name=\"__viewstate\"");
        if (StartPoint >= 0)
        {
            int EndPoint = html.IndexOf("/>", StartPoint) + 2;
            string viewstateInput = html.Substring(StartPoint, EndPoint - StartPoint);
            html = html.Remove(StartPoint, EndPoint - StartPoint);
            int FormEndStart = html.IndexOf("</form>") - 1;
            if (FormEndStart >= 0)
            {
                html = html.Insert(FormEndStart, viewstateInput);
            }
        }
        writer.Write(html);
    }


}








11.5.ViewState
11.5.1.Disable ViewState for a certain control
11.5.2.Trim view state
11.5.3.Use ViewState to store object list (C#)
11.5.4.Use ViewState to store object list (VB)
11.5.5.Insert view state data in Page render event (C#)
11.5.6.Insert view state data in Page render event (VB)