Head Rush Ajax

92

Chapter 2

Well, we’ve got to run the createRequest()

function somehow, right? How else can we

create the request object?

Remember how we declared the request variable, but didn’t put

that line of code in a function?

JavaScript doesn’t have to be in a function

<head>

<title>Break Neck Pizza Delivery</title>

...

<script language=”javascript” type=”text/javascript”>

var request = null;

</script>

</head>

This code will run automatically

when the page loads.

By the time the page

is loaded, a new variable,

called request...

...should be pointing at an

instance of a JavaScript

request object.

Any JavaScript in your web page that’s not in a function gets run

statically. That means that as the web browser is loading your page,

it will automatically run any JavaScript it nds that is not in a function,

before anyone can type into your form or click any buttons on the page.

So if we move all of the code in createRequest() out of a

function, all the code that tries to create the request object will run as

soon as the Break Neck form loads. If there are errors, customers will

know right away... and getCustomerInfo() won’t need to run

createRequest() anymore—the request object will be ready to

use, or the customer will have already received an error message.

request

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Request Object

Man, Break Neck pizza rocks. There’s

nothing like a breakfast of cold pizza, ...