Our order form sent its data to a file called processorder.php via the instruction:
ACTION="processorder.php"
method=post
This is the content of
that file:
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
<title>Acme Widget Company</title>
</head>
<body style="font-family: Arial">
<h1><br>
Acme Widget Company</h1>
<p> </p>
<?php
$qtybases = $_POST[’qtybases’];
$qtystems = $_POST[’qtystems’];
$qtytops = $_POST[’qtytops’];
?>
<p>Thank you!</p>
<p>Your order for:</p>
<?php
echo $qtybases.’ bases<br>’;
echo $qtystems.’ stems<br>’;
echo $qtytops.’ tops<br>’;
?>
<p>was processed.</p>
</body>
</html>
(File Content ends above
this line)
In here there’s plenty
of interesting PHP code to take a look at! We’ll start with that first
piece of PHP code:
$qtybases = $_POST[’qtybases’];
$qtystems = $_POST[’qtystems’];
$qtytops = $_POST[’qtytops’];
(To make life easier, I’ve left off the opening and closing tags when looking at
the code itself & I’ll continue like that throughout this series.)
Each of these statements is an "assignment" instruction. The equal sign in
the middle designates it as such and tells PHP to "make the value of this Equal
to the value of that." In this case we’re making the value of one variable
equal to the value of another variable (a "variable" is a data element whose
value can change, as opposed to a "constant" which is a data element whose value
can not change.)
The variables on the
left, $qtybases for example, are variable fields that are being dynamically
defined by these statements. This means that no other statement was needed
to create the variable $qtybases; it’s being defined right here. Those
variables are being set to the values of some "POST" variables.
"POST" variables are those that are passed down from the preceding form by means
of the POST method (remember the statement
<FORM ACTION="processorder.php" method=post> in the form.)
We’ll get into more detail about these variables later; for now suffice it to
say that this format, using the names that were used in the calling form, will
pick up the variables being passed down.
Then there’s that group
of echo statements. "Echo" works like a "print here" command.
Remember that the PHP processor is going to interpret the PHP code in this page
and then send the page down to the client browser. Whatever the echo
prints out becomes part of the resulting page. Each of these echo
statements prints out the value of a variable and a text string enclosed in
quotes. Look closely and you’ll see a period between the two This
tells PHP to concatenate the two strings (the value of the variable and the
quoted string) together. Thus, if $qtybases has a value of 5 then the
first echo statement will return this:
5 bases<br>
which, on the resulting
web page, will show up as "5 bases" followed by a line break.
Try it out on
our example.
