Dreamweaver MX

Shubhada · April 7th, 2004, 04:55 AM

Hi Imar!

As a practice, I have written a simple program (based on your try it out in chapter 11) where there is a form with just 2 inputs. One is a text field and the other is a submit button. When I type the color in the textbox and click the button, the web page should change its own background-color according to the color given the textbox of the form. However when I open the page in the browser following happens:

1. For the first time when I open the page in the browser and type the color (e.g. #CCCCCC) in the textbox, nothing happens â the page remains white.
2. The second time when I type the color and click the button, the following error message is displayed:

--------------------------------------------------------------------------------------------------------------------------------
Response object error 'ASP 0156 : 80004005'
Header Error
/cookietrial/changeColor.asp, line 4
The HTTP headers are already written to the client browser. Any HTTP header modifications must be made before writing page content
----------------------------------------------------------

I have pasted the code below. Could you please tell me what is wrong with it?

----------------------------------------------------------
<%@LANGUAGE="VBSCRIPT" CODEPAGE="1252"%>
<%
    If Request.Form("btnColor") <> "" Then
        Response.Cookies("BackGroundColor") = Request.Form("txtColor")
        Response.Cookies("BackGroundColor").Expires = Date() + 30
    End If
    Dim sBackgroundColor
    If Len(Request.Cookies("BackGroundColor")) > 0 Then
        sBackgroundColor = Request.Cookies("BackGroundColor")
    Else
        sBackgroundColor = "#FFFFFF"
    End If

%>
<html>
<head>
<title>Untitled Document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</head>

<body style="background-color: <%= sBackgroundColor %>" >
<form action="changeColor.asp" method="post" name="frmColor"><input name="txtColor" type="text" value="">
  <input name="btnColor" type="submit" value="Change Background Color"></form>
</body>
</html>
------------------------------------------------------

Thanks.

Shubhada

Imar · April 7th, 2004, 05:07 AM

I knew that would happen.... ;)

Check out page 310, under the heading "Forewarned is Forearmed"...

Cheers,

Imar

---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.

Shubhada · April 7th, 2004, 06:20 AM

Hi Imar!

Thanks. I shuffled the code around and it is working now.

But why should it so happen when all I was doing was setting the value of the variable âsBackgroundColorâ before writing the cookie? I was not outputting any content to the browser before writing the cookie.

Shubhada.

Imar · April 7th, 2004, 06:28 AM

Are you use you didn't sent any content to the browser? Even spaces and tabs can cause this problem.

I copied and pasted your code to a PWS installation on Windows ME (I finally got to setting it up under Virtual PC) and it ran fine immediately....

Imar

---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.

Shubhada · April 7th, 2004, 06:29 AM

Hey...wait..wait!!
I did shuffle the code - but shuffled it 2-3 times. And finally when it is working, the statements are in exactly in the same order as before.

<%
    If Request.Form("btnColor") <> "" Then
        Response.Cookies("BackGroundColor") = Request.Form("txtColor")
        Response.Cookies("BackGroundColor").Expires = Date() + 30
    End If
    Dim sBackgroundColor
    If Len(Request.Cookies("BackGroundColor")) > 0 Then
        sBackgroundColor = Request.Cookies("BackGroundColor")
    Else
        sBackgroundColor = "#FFFFFF"
    End If

%>
And now it is working. The same order of statements was not working before. Effectively, nothing is changed, then why so?

Shubhada.

Shubhada · April 7th, 2004, 06:32 AM

Our responses crossed.

Yes, may be some tab or space was inserted in the previous code, which was removed while shuffling - so now it is working.

Were you able to reproduce my previous error (uppercase variables) on ME+PWS?

Shubhada.

Shubhada · April 7th, 2004, 06:35 AM

I checked both the codes. There was no tab or space in my previous code. I also did not send any other content to the browser. Still it was not working.

Shubhada.

Imar · April 7th, 2004, 06:37 AM

Not yet. I *just* got it working. In fact, I just finished the install procedure after I received this post, so I could take a look and see if it was a PWS issue.

The install procedure didn't go so easy. The downloader file for PWS is no longer able to download the correct files automatically, so it took me a while to figure out what to do.

I'll try the app var issue later today, hopefully.

Imar

---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.

Imar · April 7th, 2004, 06:46 AM

Right. I was just able to reproduce the UCase issue. I set a few Session and App vars, and this is what I got when I ran the test page that dumps the Session and Application variables:

STARTTIME : 4/7/2004 1:43:55 PM
TEST : Test Value
List of 2 items in Application contents collection:
-----------------------------------------------------------
TOTALNUMBEROFUSERS : 1
CURRENTNUMBEROFUSERS : 1

So, also on my PWS installation, the names of the vars are uppercased. I still haven't found out whether this is a known issue or not, but it sure is something to remember.....

Does the cookie code still work?

Imar

---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.

Shubhada · April 7th, 2004, 07:26 AM

Yes, the cookie code is still working.

Shubhada.