title: ASP.NET C# - How to retain value after Response.Redirect
body: <p>I'm working in ASP.NET c# application.
  I came to a part where I need to retain some value after response.redirect to the same page <strong>without using additional QueryString or Session</strong>, because Session more or less may burden the server's performance even just a small value.</p>
  
  <p>Below is my code fragment:</p>
  
  <pre><code> protected void ddl_SelectedIndexChanged(object sender, EventArgs e)
   {
  string id = ddl.SelectedValue;
  string id2 = ddl2.SelectedValue;
  Response.Redirect("http://sharepoint2007/sites/home/Lists/CustomList/DispForm.aspx?ID=" + id);
   }
  </code></pre>
  
  <p>I wanted to retain the value id2 after the Response.Redirect, I've tried ViewState but seem like after the redirect, it treat the page as new page and ViewState value gone.</p>
  
  <p><strong>Update:</strong></p>
  
  <p>My intention to retain the value after redirect is wanted to bind back the dropdownlist selected value.</p>
  
  <p>Please help.</p>
  
  <p>Thank you in advanced.</p>