Basic: Calling variable in ASPX from XML

DolphinBay · April 20th, 2004, 02:25 PM

Good afternoon all,

Pardon my newbie question. I am trying to call a variable out of an XML file I created and I am getting the following error:

BC30451: Name 'cfgManager' is not declared

The offending line reads:

<% Response.Write(cfgManager.getSetting("BASE_HREF")) %>

If I place this line in the Page_Load sub (without the <%, %> delimiters of course) within the code-behind it works fine. While this example will not be used in a real-world app I am trying to get my hands around passing information from an XML file to the ASPX file.

Many thanks.

Dolphin Bay, Inc. -- turning visions into eReality(tm) -- West Palm Beach, FL
Website Design, Internet Strategy, Search Engine Marketing

www.DolphinBay.biz

planoie · April 20th, 2004, 06:55 PM

Can you post what's around that offending line? The context of it would be helpful. Are you saying that the offending line is inside a .xml file?

DolphinBay · April 20th, 2004, 09:09 PM

Minus the standard code that VS.Net adds to a webform, the offending line is pretty much all that I added to the file. Below please find the entire aspx file:

<%@ Page Language="vb" AutoEventWireup="false" Codebehind="home.aspx.vb" Inherits="test.home"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
    <HEAD>
        <title>home</title>
        <meta name="GENERATOR" content="Microsoft Visual Studio .NET 7.1">
        <meta name="CODE_LANGUAGE" content="Visual Basic .NET 7.1">
        <meta name="vs_defaultClientScript" content="JavaScript">
        <meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5">
    </HEAD>
    <body MS_POSITIONING="GridLayout">
        <form id="Form1" method="post" runat="server">
            <% Response.Write(cfgManager.getSetting("BASE_HREF")) %> <--- OFFENDING LINE OF CODE
        </form>
    </body>
</HTML>

And here is the content of the XML file, again very basic:

<?xml version="1.0" encoding="utf-8" standalone="yes" ?>
<applicationSettings>
        <BASE_HREF>http://localhost/</BASE_HREF>
</applicationSettings>

The vb file reads the members of an XML file and caches the information. Like I said in my previous email, I know it works when I call the cfgManager class in the code-behind, I just would like to get it to work in the actual ASPX file.

Many thanks for the help.

Dolphin Bay, Inc. -- turning visions into eReality(tm) -- West Palm Beach, FL
Website Design, Internet Strategy, Search Engine Marketing

www.DolphinBay.biz

Imar · April 21st, 2004, 01:50 AM

Hi there ,

You'll need to fully qualify the cfgManager class. That class is not accessible directly in the "Code Before" of your page. Something like this should work:

Code:

<form id="Form1" method="post" runat="server">
  <% Response.Write(test.home.configuration.cfgManager.getSetting("BASE_HREF")) %>
</form>

This code assumes that the cfgManager class lives in the test.home.configuration namespace.

Cheers,

Imar
---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.
While typing this post, I was listening to: Rob D - Clubbed To Death (kurayamino mix) by The Matrix (Track 4 from the album: The Matrix - Movie Soundtrack)

planoie · April 21st, 2004, 06:15 AM

Something you should look into is getting away from the ASP style inline code. Instead of an inline <% Response.Write ... %> use one of the many web controls available like a Label or Literal. Then you can set that control's property in the code behind where you don't have the access problem.

DolphinBay · April 21st, 2004, 08:08 AM

I would love to get away from using inline code. Do you have any suggestions how I can go about solving this task with an alternate form of coding?

I am trying to use a constant value from an XML file within a javascript code snippet, see below:

var frameRelocate = "<% Response.Write(cfgManager.getSetting("BASE_HREF")) %>";
  if(parent.frames.length == 0) {
    if(document.images) {
      location.replace(frameRelocate);
    } else {
      location = frameRelocate;
    }
  }

As the BASE_HREF value will obviously change based on the domain running the app, I want to incorporate it into an XML constants file, rather than having to manipulate the code or the web.config file for each installation.

Dolphin Bay, Inc. -- turning visions into eReality(tm) -- West Palm Beach, FL
Website Design, Internet Strategy, Search Engine Marketing

www.DolphinBay.biz

Imar · April 21st, 2004, 08:21 AM

Hi there,

You could use a Literal control embedded in your JavaScript in the ASPX page. That allows you to change its Text property from within the Code Behind page, like this:

Code:

[ASPX Page]
<form id="Form1" method="post" runat="server">
    <script type="text/javascript">
      var frameRelocate = '<asp:literal id="Literal1" runat="Server" />';
    </script>
</form>

And then in your code behind add a declaration for the control:

Code:

protected  System.Web.UI.WebControls.Literal Literal1;

Finally, from within a method in the page class, like Load, you can change the inner text of the Literal control like this:

Code:

Literal1.Text = "Your Base URL Here";

Instead of the hard coded value, you can of course use any method that returns your Base URL.
The JavaScript in your page will now end up like this:

Code:

<script type="text/javascript">
var frameRelocate = 'Your Base URL Here';
</script>

Hope this helps,

Imar
---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.
While typing this post, I was listening to: Mope by Bloodhound Gang (Track 5 from the album: Hooray for Boobies)

DolphinBay · April 21st, 2004, 08:32 AM

Imar,

That did the trick. Thank you for the valuable information regarding the use of literals.

Regards,
Eric

Dolphin Bay, Inc. -- turning visions into eReality(tm) -- West Palm Beach, FL
Website Design, Internet Strategy, Search Engine Marketing

www.DolphinBay.biz

Imar · April 21st, 2004, 08:36 AM

You're welcome.

Like Peter said, using ASP.NET Controls is much better than using "old skool" Response.Write and <% %> constructs. Using the controls allows you to fully separate the code from the design, so you can stay far away from the old spaghetti style coding techniques [not sure if that is good for Italian export, though ;)]
Cheers,

Imar
---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.
While typing this post, I was listening to: Lillies Dying by Curve (Track 5 from the album: Doppelganger)

planoie · April 21st, 2004, 08:42 AM

I have used that same technique that Imar suggested. Lately, I have been doing something which I find a little less awkward than that. Instead of embedding literals within the javascript itself, I put the whole javascript block in a literal and use replacement tokens in the JS code:
<asp:literal id="Literal1" runat="Server">
   <script type="text/javascript">
      var frameRelocate = '[%FRAMERELOCATE%]';
      var intSomeInteger = [%ANOTHERVAR%];
   </script>
</asp:literal>

In the code-behind, I only need to have one class instance of a literal control:

   Protected Literal1 As System.Web.UI.WebControls.Literal

Then in the page load, or wherever is appropriate, I replace the tokens with real values:

Literal1.Text = Literal1.Text.Replace("[%FRAMERELOCATE%]", strFrameRelocate)
Literal1.Text = Literal1.Text.Replace("[%ANOTHERVAR%]", intMyInteger)

If you have to put a lot of server side values into client side script, I find this to be a little cleaner and easier way to deal with the values.