Using Variables inside variables

calvinmickle

I would like to build a content page that is called by an "include" construct. This page would contain all the information relavent to that particular content subject.

My wrapper pages are constructed with a header file, two sidebars (left and right), content in the center, and a footer.

If I call the center content after the header, I cannot have the header information (meta tags, keywords, title, etc.) moved backwards to the header space.

I am considering calling the include construct for the content before the header, but making each piece of information a variable which can be used later in the page, so that in the center, instaed of include center, I would have echo $center.

I know diddly about databases, and this is the easiest thing I can think of. So the question is ...

How do I handle using an entire page of HTML formatted code, which would include variables inside of strings, inside a variable?

Or, is there an esier way?

Many thanks.

laserlight

You could use [man]eval/man, but there should be some better way to re-arrange your code so that output is not sent before headers are sent.

If all else fails, output buffering should be better (and perhaps safer) than eval() anyway.

Roger_Ramjet

You could use an iframe for the content, the content headers would be in the iframe. No problem

You could use XMLHttpRequestor. same as above but differnt method

You coild use content files without headers. Why do you want them anyway, search engines?

Both of the above would allow you to change content without reloading the whole wrpper page, looks a lot slicker to the user than reloading the whole page.

calvinmickle

Hi Laserlight,

Thanks for responding to another of my cries for help. So what is output buffering?

Hello Roger Ramjet,

Yes, I want the header stuff for search engines, so that each page gets read differently when it is spidered. I can create a lot of info on my subject, and each page is identified from as many aspects as possible.

Would the search engine spider then spider the iframe? How would that affet the identification of the master page by the spider?

I'm going to the link on your post, but what is an XMLHttpRequestor?

Many thanks to both of you.

You both seem to be regulars here, and seem to be very helpful.

Roger_Ramjet

The contents of the iframe would be your files with all of their headers and content. If that content is dynamic then spiders will have the same problem however it is displayed. Otherwise, a spider will treat them just as it would if they were being linked to on their own and not in a frame.

xmlhttprequestor is a way to include XML data in a page dynamically and without the need to reload the whole page. Call it an XML iframe, though of course it's not. See the demo you'll just love the functionality

TheDefender

The only thing is the lack of truly global support by the browsers when using iframes, so be careful if you go that route.

This page has some good info on iframes.

calvinmickle

Thanks Roger,

Thanks Defender,

Took a look at the XMLHttpRequester. It is way above my head (four days into PHP, after seven days into .htaccess RewriteRule, after a not so long time of using Notepad to build an HTML page).

Use an iFrame now on my site, as a pop-up window for email subscription registration. A little JavaScript frameless iFrame (don't ask me, it was cut and paste till it worked). For where JavaScript is disabled, or iFrames don't work, I have a click link as a catch-all. One day I hope to learn how to code for browsers, but I'm a slow learner, an old fogey pensioner trying to keep up with you guys.

So far, at my skill level, I'm probably back to putting the content in a variable and seeing how to use variables in that content.

I'm thinking of ...

<? session_start ... ?>
<? include("MyContent.php") ?>
<HTML>
<head>
<Meta Something <? echo $var1_FromMyContent ?> 
</head>
<body>
<? include("MyHeader.php") ?>
<? include("MyLeftSidebar.php") ?>
<? echo $var2_FromMyContent ?>

<? include("MyRightSidebar.php") ?>
<? include("MyFooter.php") ?>
</body>

<!-- An example of a variable in $var2_FromMyContent $ -->
<a href=$a_Session_Variable >

As you can see, I plan on using session variables inside the HTML that is inside the mycontent part that is one of the variables in that document.

The mycontent.php document would contain several declarations for variables. Nothing that should remain after the PHP is parsed. One variable for each part of the <head> that needed to be updated with the page, and one big one for the center cell where the links with variables are used.

Can this work, or is there an easier way for someone with my skill level?

Can this work?

Roger_Ramjet

Well, yes I'm sure that it can be made to work. I also think it is the most difficult approach to make work.

Forget the javascript iframe, just use a standard html iframe . If someone is still using a no-frames ver 4 browser then that is their problem, seriously. Can't think who would be or why, even on a winders95 machine. And the javascript iframe would probably be even less functional on it.

Table for layout is it? An html iframe in a table cell is easy-peasy. Read the link for how to target the iframe with the selected link. Take it a bit at a time. Get that working first and then go on to the version 2: parsing one page into another as you are about to try. It just helps to build confidence to have something working; because I'm sure the other approach will take a long time to get right.

calvinmickle

Hello Roger,

Thanks.

Got the iFrame thing down, and have used it. The javascript thing was "cute," hence the inclusion. I'll work on another method of getting the signup form on the same page.

I just tested the method I described to you and it was reasonably easy, except for the fact that the php code in my variable was treated as string text and only showed up in the source.

Here's the source from the wrapper ---

<?
// Start the session and register the variables
SESSION_START();

header("Cache-control: private");
SESSION_REGISTER("EmptyField");
SESSION_REGISTER("Affiliate");
SESSION_REGISTER("LandingPage");
SESSION_REGISTER("CurrentPage");

$URL_data = explode("/", getenv("REQUEST_URI"));

// Get tracking information form the URL array
$SESSION['EmptyField'] = $URL_data[0] ;
$SESSION['Affiliate'] = $URL_data[1] ;
if ($LandingPage == "") {
$SESSION['LandingPage'] = $URL_data[2] ; }
$SESSION['CurrentPage'] = $URL_data[2] ;

// Fill in the blanks on the page header
$ThisPageName = ucfirst($CurrentPage);
include $CurrentPage . '.php' ;
?>
<html>
<head>
etc.

Here is the stuff from the center cell (I use two methods to see how it works - I know the include method works) ---

<td class="cont"> 
<?php include "myphpform.php"; ?> 
***************** Variable appears below ***************** 
<? echo $var2 ?>
</td>

Here are the contents of myPHPcontent.php before rendering

<? $var1="Some Content" ?>
<? $var2 = "
The variable starts here 
Empty Field? = <?php echo $EmptyField; ?> 
Affiliate Num? = <?php echo $Affiliate; ?> 
Landing Page? = <?php echo $LandingPage; ?> 
Current Page? = <?php echo $CurrentPage; ?> 
" ?>

Here's the output of the myphpform.php comapered to the output of the output from the myPHPcontent.php variable $var2 as shown in the browser

The include starts here
Empty Field? =
Affiliate Num? = 10015
Landing Page? = myPHPcontent
Current Page? = myPHPcontent
***************** Variable appears below *****************
The variable starts here
Empty Field? =
Affiliate Num? =
Landing Page? =
Current Page? =

and as shown in the browser source

<td class="cont"> 
The include starts here 
Empty Field? = 
Affiliate Num? = 10015 
Landing Page? = myPHPcontent 
Current Page? = myPHPcontent 
***************** Variable appears below ***************** 
The variable starts here 
Empty Field? = <?php echo ; ?> 
Affiliate Num? = <?php echo 10015; ?> 
Landing Page? = <?php echo myPHPcontent; ?> 
Current Page? = <?php echo myPHPcontent; ?> 
</td>

I feel like I have a mistake in the myPHPcontent file. Could you look at it and advise?