PHP include file multiple times in one page

Question 1

I have a php-file called kal_test.php which gives a value to the variable $vbl. This variable is needed in the file called kal_generator.php which produces a table from that variable (I'll spare you the details). It goes like this:

[kal_test.php]

<?php
$vbl = "14/09/2011";
include ("kal_generator.php");
?>

[kal_test.php]

<?php
// Long code converts the $vbl into a 2-dimensional array called $output
// I'll spare you the details (it works fine by the way)
?>

<table>
  <tr><th>bla</th><th>blabla</th></tr>

<?php
foreach ($output as $v1) {
    echo "<tr>";
    foreach ($v1 as $v2) {
        echo "<td>$v2</td>";
    }
    echo "</tr>n";
}
?>

</table>

This set-up works fine but I can't make two of those appear on the same page, like this:

[kal_test.php]

<?php
$vbl = "14/09/2011";
include ("kal_generator.php");
$vbl = "21/09/2011";
include ("kal_generator.php");
?>

This will give the following result:

//here comes the header

<table> // table created with $vbl = "14/09/2011"
  <tr><th>bla</th><th>blabla</th></tr>
  <tr><td>this</td><td>works</td></tr>
  <tr><td>this</td><td>works</td></tr>
</table>

//here should the second table be and also the rest of the page (footer), this is completely missing

What am I doing wrong? Thanks!

Question 2

You're likely defining a function or class in kal_generator.php. PHP aborts when you try to redefine such a function or class. Consider putting your code in a function, include that function once and then run the function instead of including a file.

kal_test.php

<?php
require_once 'kal_generator.php';
kal_generator("14/09/2011");
kal_generator("21/09/2011");
?>

kal_generator.php

<?php
function kal_generator($vbl) {
    /**
     * Here, you should be creating $output
     */
    echo <<EOF
<table>
  <tr><th>bla</th><th>blabla</th></tr>

EOF;
    foreach ($output as $v1) {
        echo "<tr>";
        foreach ($v1 as $v2) {
            echo "<td>$v2</td>";
        }
        echo "</tr>n";
    }

    echo "</table>n";
}
?>

Question 3

Your best solution would be to store your retrieved data in an array, which you can then use whenever you want without having to make more queries to your database, like so:

// First we make the query and store the rows in an array
$result = mysql_query($query);
$data_array = array();
while ($data = mysql_fetch_assoc($result)) {
    $data_array[] = $data;
}

// Then we can loop through the values in that array without making further queries
echo '<ul class="menu">';
foreach ($data_array as $data) {
    echo '<li><a href="page.php?id=', $data['id'], '">', $data['title'], '</a>';
}
echo '</ul>';

// Another loop through our array
echo '<ul class="sitemap">';
foreach ($data_array as $f_data) {
    echo '<li><a href="page.php?id=', $f_data['id'], '">', $f_data['title'], '</a>';
}
echo '</ul>';

Question 4

The easiest way for the generic "PHP app running on an Apache server that you may or may not fully control" situation is to put your includes in a directory and deny access to that directory in your .htaccess file. To save people the trouble of Googling, if you're using Apache, put this in a file called ".htaccess" in the directory you don't want to be accessible:

Deny from all

If you actually have full control of the server (more common these days even for little apps than when I first wrote this answer), the best approach is to stick the files you want to protect outside of the directory that your web server is serving from. So if your app is in /srv/YourApp/, set the server to serve files from /srv/YourApp/app/ and put the includes in /srv/YourApp/includes, so there literally isn't any URL that can access them.

Question 5

You can't include php files relatively to your webroot that way, cause if you use the slash as first character, the reference will go much deeper than just your document root. So, instead of using your basepath, you could do something like this :

<?php 
   $path = $_SERVER['DOCUMENT_ROOT'];
   $path .= "/yourpath/yourfile.php";
   include_once($path);
?>

Question 6

#include "file" means take the header file and put all of its content instead of the #include line.

We usually used headers for type definitions and for adding a forward declarations to a source files. defining same type twice in a file (a circular include will always cause it) gives compilation error, therefore we use #ifndef or #pragma once. (or both)

But we also can to put a repeating code and macros and include it several times, even in the same file. in such as case, we won't use #ifndef nor #pragma once. If you do so you must be extra careful, and do it only if you know what you are doing.

For example: If in some OS calling a specific system function (or even a c macro like: offsetof) cause a bunch of warnings, and it is bothering you, and you sure your code is good, but you don't want to disable all the warnings you've got on all the project or the file, you just want to disable it when you call the specific function.

//suppress the warnings: 
#if defined(__GNUC__)
  #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
    #pragma GCC diagnostic push
    #pragma GCC diagnostic ignored "-Wreorder"
    #pragma GCC diagnostic ignored "-Wunused-function"
    #pragma GCC diagnostic ignored "-Wunused-variable"
    #pragma GCC diagnostic ignored "-Wsign-compare"
    #pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
    #pragma GCC diagnostic ignored "-Wsequence-point"
  #endif
#endif // __GNUC__

//here you call the function...
func(x,y,z);

//unsupress: bring back the warnings to normal state
#if defined(__GNUC__)
  #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
    #pragma GCC diagnostic pop
  #endif
#endif // __GNUC__

This will make your code to look very dirty, especially if you call the function several times.

One possible solution, (I'm not suggesting it is the best one...) is to make 2 headers, in one to suppress the warnings and in the other to cancel the suppression.

In that case your code may look like this:

#include "suppress.h"
func(x,y,z);
#include "unsuppress.h"

//.... more code come here 
//now when call it again:
#include "suppress.h"
func(x,y,z);
#include "unsuppress.h"

PHP include file multiple times in one page

Answers

kal_test.php

kal_generator.php

php,include