Head Rush Ajax

you’re on your way 4

23

next generation applications

That’s all the server sends back now? I’ll

bet my report will run faster with Ajax!

I’ll have my PHP guy take care of changing

the server-side script right away.

Katie’s server doesn’t

have nearly as much

information to send

back to her web form.

When you’re writing Ajax apps, the server doesn’t need to send all that

HTML back in its response. Since you’ll use JavaScript to update the web

page, all you need from the server is the raw data. In Katie’s app, that

means that all we want is the number of boards sold. Then, you can gure

out the cash that Katie has made with some simple JavaScript.

What the server should do now

1149

getUpdatedBoardSales-ajax.php

The URL to the

new, Ajax-ready

version of the PHP.

The total number

of boards sold.

A much happier,

stress-free server.

24

Chapter 1

...at a glance

PHP

Katie’s PHP script got a lot simpler when all it needed to do was

return the total number of boards sold. Take a look:

<?php

// Connect to database

$conn = @mysql_connect(“mysql.headrstlabs.com”,

“secret”, “really-secret”);

if (!$conn)

die(“Error connecting to MySQL: “ . mysql_error());

if (!mysql_select_db(“headrst”, $conn))

die(“Error selecting Head First database: “ . mysql_error());

$select = ‘SELECT boardsSold’;

$from = ‘ FROM boar ...