Question

I have seemingly easy problem and am having trouble designing the right solution.

I have a normal asp .net login control. When the user logs in (and is successfully authenticated) I want to display a JavaScript message prompt like:

Warning: This is a government system…etc

There are a million and one ways to do this… but I really wanted to keep it inside my login user control. I played around with the following methods with no luck:

protected void OnAuthenticate(object sender, AuthenticateEventArgs e)
{
    Page.ClientScript.RegisterStartupScript(this.GetType(), "warning", "alert('hello');", true);
}

protected void OnLoggingIn(object sender, LoginCancelEventArgs e)
{
    Page.ClientScript.RegisterStartupScript(this.GetType(), "warning", "alert('hello');", true); 
}

protected void OnLoggedIn(object sender, EventArgs e)
{
    Page.ClientScript.RegisterStartupScript(this.GetType(), "warning", "alert('hello');", true);
}

It seems like the postback page lifecycle is screwing me over.

Maybe I should think about this differently?

login page -> (success) -> warning message page -> user dashboard page

Any advice would be greatly appreciated.

Thanks!

-Josh

EDIT: I’ve also tried Page.ClientScript.RegisterClientScriptBlock(“….”);

Answer 1

Are you using a master page/base page and session? you can do it this way so that the warning would be shown on the first non login page:

protected void Page_load(object sender, EventArgs e) 
{
   if (Request.IsAuthenticated && !Page.IsPostBack())     
      if (session["warningShown"] == null or session["warningShown"] == false)
      {
         session["warningShown"] = true;
         Page.ClientScript.RegisterStartupScript(this.GetType(), "warning", "alert('hello');", true); 

      }
   }
}