PHP - Fairly Simple Globals Question

Hi Guys. This should- hopefully- be a pretty simple question for someone with regex experience to answer. I've been reading all the regex guides and tried various things but none have worked and I'm starting to get a headache. I've decided to just pitch the question here.

How do I test if a string contains ONLY a certain character- but could be one or more instances of that character. In this case it's a comma. So:

','           -> Would return TRUE
',,,'         -> Would return TRUE
',,,,,,,'     -> Would return TRUE

',,,hello,' -> Would return FALSE
'hi,,,'       -> Would return FALSE


Thanks in advance!

I think this is a simple question, but I'm just starting out and can't figure out how to do this exactly.

I'm making a demo site for a flower shop. The structure is as such (only listing the particular files in question - once this is done, the rest will be easy)

index.php -> inc_show_colors.php -> showColors.php

The index is to be standard through the site, loading include files into a main content area.  Clicking on a link loads inc_by_color.php (index.php -> index.php?page=by_color )

From there, one of the four colors is selected.

showColors.php contains switch statements for each color. I want to load showColors.php into the main content window when a color is selected, and I need to have it work for all four colors. I'm not sure how to do this, as you can't pass a variable to an include from what I understand.

What's the easiest way to go about this? Keep in mind this is an intro class and "best practices" are not necessary yet, just the simplest solution to get it working.

 I want each of these colors to link to another include file, which will load in its place in index.php.


index.php:
Code: [Select]
<div id="maincontent">
<?php
if (isset($_GET['page'])) {
switch ($_GET['page']) {
case 'by_color':
include('includes/inc_by_color.php');
break;
case 'by_type':
include('includes/inc_by_type.php');
break;
case 'by_occasion':
include('includes/inc_by_occasion.php');
break;
case 'view_cart':
include('includes/inc_view_cart.php');
break;
case 'payment_options':
include('includes/inc_payment_options.php');
break;

case 'home_page':
default:
include('includes/inc_home.php');
break;
}
}
else 
include('includes/inc_home.php');

?>
</div>

inc_by_color.php:
The first link I tried doing in the way I thought would work, but it doesn't. It can't find the include file.
The second one works, kind of - but it just loads the page by itself, not into the maincontent div in index.php.
Code: [Select]
<h1>Flowers Categorized by Color</h1>
<div class="picdivcontainer">
<div class="picdiv"><a href="index.php?page=red"><img src="images/image.png" width="90" height="90" alt="Red Flowers" />
  <p>Red</a></p></div>
<div class="picdiv"><a href="showColors.php?color=white"><img src="images/image.png" width="90" height="90" alt="White Flowers" /></a>
  <p><a href="showColors.php?color=white">White</a></p></div>
</div>

and showColors.php:
Code: [Select]
if (isset($_GET['color'])) {
switch ($_GET['color']) {
case 'red':
$result = mysql_query("SELECT * FROM flowers WHERE color='red'") or die(mysql_error());
while($row = mysql_fetch_array( $result )) {
// Set and trim strings and show the resulting flowers from query
$flowername = $row['name'];
$flowerimage = $row['image'];
$image_path = "images/";
$flowername = str_replace('_', ' ', $flowername);
$flowername = ucwords($flowername);
?> <div class="picdiv"><p><?php echo $flowername."<br />";
$flowerimage = str_replace(' ', '_', $flowerimage);
echo "<img src='images/" . $row['image'] . "' />";
?></p></div> <?php
} 
break;
I realize that showColors.php is probably a really messy way of doing this, but I just need to get it functioning ASAP for now.

Imagine 6 PHP classes (one each for a product line), that have very similar coding structures, that go like this:

//function that computes stuff inside each of 6 files:
//they vary slightly from file to file but essentially it is this:
function computeFunction
{
    $this->x = new X();

    $this->x->calcD();

    if ($this->x->dOk)
    {
        $this->x->calcE();
        $this->x->calcN();   
    }

    //more complicated logic that is essentially like above

    //and by the way!
    print $this->x->someVarThatIsUsedLater;
}

Then there is a single class like so :

class X
{
    function calcD()
    {
        //compute some condition

        if (<computed condition is met>) $this->dOk = true;
        else $this->dOk = false;

        //and by the way
        $this->someVarThatIsUsedLater = 4;
    }
}

Just to bring your attention to it, none of these functions return any result or value, but they nevertheless operate on variables of key interest via side-effects.  That is, they modify variables that essentially act like globals, and then use those variables later ($this->dOk and $this->someVarThatIsUsedLater are one more prominent examples).   I need to untangle this mess.  And make it clean and clear again, and make sense.  How do I best proceed?   I have been wrestling with some ideas... like $this->dOk, can within reason be turned into a return variable of calcD() function, and then be tested against like if ($this->x->calcD()) and I think it will be reasonable enough.  But then there are other functions that don't return anything and just act on variables via side-effects anyway so $this->dOk is one of the lesser troubles...   Other than that, what I am thinking of doing is getting rid of these mini-functions (calcE(),  calcN(), etc.), removing them as a funciton, and putting their body directly into the code, as a first step to refactor.  Many of the computations done inside are just a few lines of code anyway, and the functions kind of hide a lot of side-effects that happen, instead of actually encapsulating the behavior.  So while it may be counter-intuitive to dismantle the functions that appear to be doing something that normally can be encapsulated (computing key variables E, N, etc), I think dismantling them will actually clean things up as far as collecting all the side-effects inside a single parent function thereby making them more visible.   Caveat:  while doing so I will end up with 6 copies of untangled dismantled functions, because dismantling class X and putting its content into each of the 6 product line classes will have that effect.   But my hope is that from that point I will see more clearly to start identifying places where I can start to truly encapsulating the behavior via various structures, instead of masking it.   Problems / Questions: I would like to but I am not entirely sure that I can skip that step of dismantling functions & the 6x multiplying effect. It's probably the same like skipping steps in solving polynomial equations.  Some can do it and some need to list each step of their work. And I am not entirely sure what structures I can replace it with in the end after I dismantle the functions. It also looks like a lot of work.  Is there a better way? P.S. I already put tests on computeFunction() for each product line so I can be less paranoid about hacking stuff up.
Edited by dennis-fedco, 19 January 2015 - 03:06 PM.

Almost every time when I read about globals, programmers discourage their use. I have a function where I need to send back some variables (which I will use in a query) so I need to use globals. Below is the function and query. I'm trying to figure out if it's ok to use globals in it.

function paginate($connection, $tableName) {
//the forsaken globals
global $limit; 
global $start;

//Pagination
$targetpage = "http://localhost/website/untitled2.php"; 
$limit = 4; 

//count rows
$sql = "SELECT COUNT(*) as num FROM $tableName";
$total_pages = $connection->query($sql) or die(mysqli_error($connection)); 
$row = $total_pages->fetch_assoc();
$total_pages = $row['num'];

//if there's no page number, set it to the first page
$stages = 3;
$page = isset($_GET['page']) ? $_GET['page'] : 0;
$start = empty($page) ? 0 : ($page - 1) * $limit;

// Initial page num setup
if ($page == 0){$page = 1;}
$prev = $page - 1;
$next = $page + 1;
$lastpage = ceil($total_pages/$limit);
$LastPagem1 = $lastpage - 1;


$paginate = '';
if($lastpage > 1)
{

$paginate .= "<div class='paginate'>";
// Previous
if ($page > 1){
$paginate.= "<a href='$targetpage?page=$prev'>previous</a>";
}else{
$paginate.= "<span class='disabled'>previous</span>"; }



// Pages
if ($lastpage < 7 + ($stages * 2)) // Not enough pages to breaking it up
{
for ($counter = 1; $counter <= $lastpage; $counter++)
{
if ($counter == $page){
$paginate.= "<span class='current'>$counter</span>";
}else{
$paginate.= "<a href='$targetpage?page=$counter'>$counter</a>";}
}
}
elseif($lastpage > 5 + ($stages * 2)) // Enough pages to hide a few?
{
// Beginning only hide later pages
if($page < 1 + ($stages * 2))
{
for ($counter = 1; $counter < 4 + ($stages * 2); $counter++)
{
if ($counter == $page){
$paginate.= "<span class='current'>$counter</span>";
}else{
$paginate.= "<a href='$targetpage?page=$counter'>$counter</a>";}
}
$paginate.= "...";
$paginate.= "<a href='$targetpage?page=$LastPagem1'>$LastPagem1</a>";
$paginate.= "<a href='$targetpage?page=$lastpage'>$lastpage</a>";
}
// Middle hide some front and some back
elseif($lastpage - ($stages * 2) > $page && $page > ($stages * 2))
{
$paginate.= "<a href='$targetpage?page=1'>1</a>";
$paginate.= "<a href='$targetpage?page=2'>2</a>";
$paginate.= "...";
for ($counter = $page - $stages; $counter <= $page + $stages; $counter++)
{
if ($counter == $page){
$paginate.= "<span class='current'>$counter</span>";
}else{
$paginate.= "<a href='$targetpage?page=$counter'>$counter</a>";}
}
$paginate.= "...";
$paginate.= "<a href='$targetpage?page=$LastPagem1'>$LastPagem1</a>";
$paginate.= "<a href='$targetpage?page=$lastpage'>$lastpage</a>";
}
// End only hide early pages
else
{
$paginate.= "<a href='$targetpage?page=1'>1</a>";
$paginate.= "<a href='$targetpage?page=2'>2</a>";
$paginate.= "...";
for ($counter = $lastpage - (2 + ($stages * 2)); $counter <= $lastpage; $counter++)
{
if ($counter == $page){
$paginate.= "<span class='current'>$counter</span>";
}else{
$paginate.= "<a href='$targetpage?page=$counter'>$counter</a>";}
}
}
}

// Next
if ($page < $counter - 1){ 
$paginate.= "<a href='$targetpage?page=$next'>next</a>";
}else{
$paginate.= "<span class='disabled'>next</span>";
}

$paginate.= "</div>";


}
 echo $total_pages.' Results';
 // pagination
 echo $paginate;
 
}//end function


and this is how I'm using the function. Without the globals I would get undefined vars $start and $limit used in the query below.


paginate($connection, "categories"); 

$sql = "SELECT * FROM categories ORDER BY cat_name LIMIT $start, $limit";
$cats_result = $connection->query($sql) or die(mysqli_error($connection)); 
while ($row = $cats_result->fetch_assoc()) { 
$cat_id = $row['cat_id'];
$cat_name = $row['cat_name'];
$cat_desc = $row['cat_desc'];

...etc


Am I using the globals properly? 

What does this mean?

Code: [Select]
{$GLOBALS['path']}