[Resolved] Getting 2 functions to play nice

[kilbey1]

I'm not at all sure how to get a variable in one function to be available in another function. I thought it was as easy as declaring it GLOBAL, but this doesn't work.

I have page display.php with two functions:
head();
foot();

Which display the header content and the footer content of my page.

Head() takes 3 parameters: title, category and scategory. Respectively, this sets the title for my page, and indicates which category or subcategory we are in, and the menu is display from this via a database.

Inside display.php, I include a file within the header function:

include "includes/menu.php";

...and here is where $category and $scategory are available.

From inside the footer function, I include:

include "left_column_content.php";

Just before this is called, I want to add an image ONLY IF certain conditions are met, ie:

if($category == '0' && $scategory == '0') {
     echo "Display an image";
}

So what is required to allow $category and $scategory, first available in head(), to be available in foot()?

Thanks,
Eve

[swr]

It sounds like you've tried to do this:

function head($title, $category, $scategory) {
    global $title, $category, $scategory;

That's not going to work, because the parameters are always local variables, and you're trying to declare them as global too, which is not right.

You could do $_GLOBAL['title'] = $title, but if you're going to use globals then you may as well just use globals and make the functions not require parameters.

Either pass them as parameters (to both head() and foot()), or use globals and don't pass them as parameters.

[kilbey1]

Mmm, no, not exactly what I've tried to do.

I've got head() set up like so in display.php:

function head($szTitle='',$category='0',$scategory='0') {

...with nothing set global at the moment (changed it back to default).

Then, in the page I'm displaying, I call something like:

include('display.php');
head('ERP Services','1','0'); 

However, I have my menu, breakout tables, and whatever else I want to display in left_column_content.php, which is actually included from inside display.php. Menu.php included in head(), while left_column_content.php is being included in foot().

Menu.php finds what arguments from head like so:

$category = func_get_arg(1);
$scategory = func_get_arg(2);

Now, before I even include left_column_content.php, I'd like to determine if $category is 0 and $scategory is 0 as well. I've tried to do this from just before my include of left_column_content.php in foot(); also tried from within menu.php.

Here's what it looks like:
http://www.wow-erp.com/index1.php
Basically, index1.php has no category and no subcategory, being the main page. IE:

include('display.php'); 
head('','0','0');

From within foot() just before my include of left_column_content.php, I currently have this:

	echo $category;
	if($category == '0' && $scategory == '0'){
	?>
	<div align="center"><a href="certified.php"><img src="images/wbe_logo_metal.jpg" alt="See Our Certifications" border="0"></a>
	    <?php
	}
	include "left_column_content.php";

But $category of course never echoes out.

[tekky]

you need to declare the variable OUTSIDE of the functions... the declare them INSIDE as global $varname;

examples from php.net

First, an example use of global:

Example 7-1. Using global

<?php
$a = 1;
$b = 2;

function Sum()
{
   global $a, $b;

   $b = $a + $b;
} 

Sum();
echo $b;
?>  

The above script will output "3". By declaring $a and $b global within the function, all references to either variable will refer to the global version. There is no limit to the number of global variables that can be manipulated by a function.

A second way to access variables from the global scope is to use the special PHP-defined $GLOBALS array. The previous example can be rewritten as:

Example 7-2. Using $GLOBALS instead of global

<?php
$a = 1;
$b = 2;

function Sum()
{
   $GLOBALS["b"] = $GLOBALS["a"] + $GLOBALS["b"];
} 

Sum();
echo $b;
?>  

[kilbey1]

I get an error:

Fatal error: func_get_arg(): Can't be used as a function parameter in /home/httpd/wow-erp/display.php on line 3

When I try:

$category = func_get_arg(1);
$scategory = func_get_arg(2);
function head($szTitle='',$category='0',$scategory='0') {
	global $category, $scategry;

or

$category = func_get_arg(1);
$scategory = func_get_arg(2);
function head($szTitle='',$category='0',$scategory='0') {
	$GLOBALS["category"] = $GLOBALS["category"];
	$GLOBALS["scategory"] = $GLOBALS["scategory"];

[swr]

Yikes... that is some very confused code.

Here is some code that should demonstrate how to do it, using global variables:

// These are set _outside_ any function, which 
// automaticly makes them global.
$szTitle = 'ERP Services';
$category = 1;
$scategory = 0;

function head() {
    global $szTitle, $category, $scategory;
    echo "In head(): $szTitle, $category, $scategory";
}

function foot() {
    global $szTitle, $category, $scategory;
    echo "In foot(): $szTitle, $category, $scategory";
}

head();
foot();

That will output:
In head(): ERP Services, 1, 0
In foot(): ERP Services, 1, 0

The values of $szTitle, $category, and $scategory are available in both functions because they are global.

In your case, you'd set the variables in the page you're displaying. The function definitions for head() and foot() should be in display.php. The calls to head() and foot() can be wherever you want.

[kilbey1]

That does it!

In my display page:

$szTitle = ''; 
$category = 0; 
$scategory = 0; 

function head($szTitle='',$category='0',$scategory='0') {
global $szTitle, $category, $scategory; 
etc.
}

function foot() {
global $szTitle, $category, $scategory; 
etc.
}

http://www.wow-erp.com/index1.php will show you the results. Certifications only shows up on main page, that being my intent.

Thanks!

[kilbey1]

The caveat to this is, if you try to call the if statement before menu.php is included, it will ALWAYS return 0, due to the variable being declared at the top of display.php.