Re: Warning: Cannot modify header information

From: Markus Ernst (derernst_at_NO#SP#AMgmx.ch)
Date: 01/14/04

  • Next message: Toby A Inkster: "Re: How do I prevent this from happening? (long text pushing out a fixed frame)" 
    Date: Wed, 14 Jan 2004 08:51:42 +0100

    "Markansas" <markansas61@yahoo.com> schrieb im Newsbeitrag
    news:cdi8005hkcvplh08n40mn453941v0b2858@4ax.com...
    >
    > No that code was the poll.php file itself.
    >
    >
    > I had looked into the header.php and founf that the line 6 was the
    > start of a Javascript. I removed the javascript and it all works fine.
    >
    > If there is ANY mention of javascript in the header.php <head> tags or
    > right even after the <body> the error appears.
    >
    > Also it don't matter WHAT the javascript code is, as long as there is
    > a javascript code of some sort, the error appears.
    >
    > Take OUT the javacript and all works fine.

    It is not because it is javascript but because you output something to the
    client at all. As a cookie is a http header you have to set it before _any_
    output to the client.

    My suggestion is as follows:
    - At the beginning of poll.php set 2 variables:
      $message = "";
      $displayform = 0;
    - Change all echo commands from echo "something"; to $message .=
    "something";
    - Change all display_form(); commands to displayform = 1;
    - At the position where poll.php is included now replace it by:
      echo $message;
      if(displayform==1) display_form();
    - Include the poll.php script at the very top of the code in the main page,
    or at least _before_ any <html> or <doctype> tags

    Now the cookie is set before the output starts.

    HTH
    Markus

  • Next message: Toby A Inkster: "Re: How do I prevent this from happening? (long text pushing out a fixed frame)"

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