PHP and MySQL Web Development 4th Ed-tqw-_darksiderg

Adding Dynamic Content
21
The following is a C-style, multiline comment that might appear at the start of a
PHP script:
/* Author: Bob Smith
Last modified: April 10
This script processes the customer orders.
*/
Multiline comments should begin with a /* and end with */. As in C, multiline comments
cannot be nested.
You can also use single-line comments, either in the C++ style:
echo ‘Order processed.’; // Start printing order
or in the shell script style:
echo ‘Order processed.’; # Start printing order
With both of these styles, everything after the comment symbol (# or //) is a comment
until you reach the end of the line or the ending PHP tag, whichever comes first.
In the following line of code, the text before the closing tag, here is a comment,is
part of a comment.The text after the closing tag, here is not, will be treated as
HTML because it is outside the closing tag:
// here is a comment ?> here is not
Adding Dynamic Content
So far, you haven’t used PHP to do anything you couldn’t have done with plain HTML.
The main reason for using a server-side scripting language is to be able to provide
dynamic content to a site’s users.This is an important application because content that
changes according to users’ needs or over time will keep visitors coming back to a site.
PHP allows you to do this easily.
Let’s start with a simple example. Replace the PHP in processorder.php with the
following code:
You could also write this on one line, using the concatenation operator (.), as
In this code, PHP’s built-in date() function tells the customer the date and time when
his order was processed.This information will be different each time the script is run.
The output of running the script on one occasion is shown in Figure 1.3.