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PHP

Posted by Fabio Neto da Silva
Fabio Neto da Silva
12,440 Points

Question about function on Mike 4 Shirts project

Hello,

On this function:

function get_list_view_html($product) {

$output = "";

$output = $output . "<li>";
$output = $output . '<a href="' . BASE_URL . 'shirts/' . $product["sku"] . '/">';
$output = $output . '<img src="' . BASE_URL . $product["img"] . '" alt="' . $product["name"] . '">';
$output = $output . "<p>View Details</p>";
$output = $output . "</a>";
$output = $output . "</li>";

return $output;

}

I understand what this function does! its displays our list of products, right! But i have a question:

Why do you need to create an empty $output variable ex.( $output = ""; ) Why is that necessary?

Thank you

1 Answer

Randy Hoyt
STAFF
Randy Hoyt
Treehouse Guest Teacher
Randy Hoyt
Randy Hoyt
Treehouse Guest Teacher

Good question! It isn't strictly necessary, but I find it works well to prevent errors in the future for two reasons.

(1) Some earlier code might use a variable name $output, and it might not be blank to start. Explicitly setting it to blank makes sure I won't have any extra text.

(2) Imagine this code:

$name = $first;
$name = $name . " " . $middle;
$name = $name . " " . $last;

Now imagine that you want to add the person's title before the name. It would be easy but wrong to add a line like this:

$name = $title . " ";
$name = $first;
$name = $name . " " . $middle;
$name = $name . " " . $last;

See why that doesn't work? You set the name to the title, but then you set it to the first name and lose the title. You can spend a lot of time trying to figure out why the title isn't showing up. Is your file not saving? Are you working in the wrong environment? I have found it works well to create the variable empty first and then concatenate everything to the end of it:

$name = "";

$name = $name . $first;
$name = $name . " " . $middle;
$name = $name . " " . $last;

Then when I go to add something at the beginning, I don't have to change the line with $first to use concatenation and I'm less likely to make a mistake.

$name = "";

$name = $name . $title . " ";
$name = $name . $first;
$name = $name . " " . $middle;
$name = $name . " " . $last;

Does that help?

Fabio Neto da Silva
Fabio Neto da Silva
12,440 Points

Yes, Thanks Randy.