PHP: Displaying only four shirts

Question

Can someone explain to me, in layman's terms, why this code:

$list_view_html = get_list_view_html($product_id,$product) . $list_view_html;

changes the order of the shirts being displayed?

I would imagine that the order of shirts would be determined by the way you call the $position variable that knows what number shirt you're on.

Using a blank variable called $list_view_html and then simply concatenating the function on it seems like voodoo to me. How and why does it work this way?

I can't seem to wrap my head around it.

Here's the full code for context:

<div class="section shirts latest">

            <div class="wrapper">

                <h2>Mike&rsquo;s Latest Shirts</h2>

                <?php include("includes/products.php"); ?>

                <ul class="products">
                        <?php 
                        $total_products = count($products);
                        $position = 0;
                        $list_view_html = "";
                        foreach($products as $product_id => $product) { 
                            $position = $position + 1;
                            if ($total_products - $position < 4) { //If this number here is less than 4, if there are fewer than 4 shirts left after this one, then we know we are looking at one of the last 4 shirts.
                            $list_view_html = get_list_view_html($product_id,$product) . $list_view_html;

                            }
                        }
                        echo $list_view_html; 
                    ?>                      
                </ul>

            </div>

        </div>

Answer 1 · 2014-05-18T20:11:26Z

May 18, 2014 8:11pm

The function, as you allude to above, is not meant to change the order in which the shirts are displayed, instead, this function is simply displaying the last 4 shirts out of all the shirts.

Basically, as the comment says for the if statement, you know you are looking at one of the last 4 shirts once that if statement passes as true, which then lets you use the last 4 as your latest 4 shirts.

As for the function and appending strings, all the function does is create a block of html code for each shirt, so you start with a blank variable, add the result of the function to it, which is the first shirt, and then you add that code to the result of the second function which is the second shirt and so on. All this is doing is basically creating one big output block of html string that eventually displays your 4 shirts.

Answer 2 · 2014-11-02T23:34:18Z

November 2, 2014 11:34pm

Oh, i get it now.

In the case:

$list_view_html = get_list_view_html($product_id,$product) . $list_view_html;

It's simply placing the new shirt to the left side of the shirt that was added before them.

This is the logic.

The arrows here represent the order of the shirts, the Yellow was the first to be added, so it stays as first.

You must read left to right.

example:

Blank

Yellow <-- Blank

Grey <-- Yellow

blue <-- Grey, yellow

You are adding blue to the left side of Grey and Yellow because the code already loop this two before

Then:

Red <-- Blue, Grey, Yellow

same as

get_list_view_html($product_id,$product) . Blue, Grey, Yellow

or

get_list_view_html($product_id,$product) . $list_view_html;

the variable $list_view_html was empty at first, then Yellow was added to it, then Grey, Blue and so on.

So if you put $list_view_html before get_list_view_html($product_id,$product) it will work the other way around.

Blank --> Yellow

Yellow --> Grey

Yellow, Grey --> Blue

Yellow, Grey, Blue --> Red

same as

Yellow, Grey, Blue . get_list_view_html($product_id,$product)

After you have 4, the loop ends and you have those 4 shirts displayed as html.

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M Fen

M Fen

PHP: Displaying only four shirts

2 Answers

Gareth Borcherds

Gareth Borcherds

Marcin Lipski

Marcin Lipski

Hugo da Silva Ribas

Hugo da Silva Ribas