Head Rush Ajax

you’re on your way 4

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xml requests and responses

And now I can just use the DOM

to work with my XML, and send

over the DOM tree.

Look at the “Content-Type” request header on

the last page... it’s “text/xml”. That tells the

server that it can expect XML, but in a text

format. That’s not the same as a DOM tree.

In fact, there’s no easy way to send a DOM tree

to a web server. You’d basically have to write

code that parses the DOM tree in reverse; it

would need to take each node in the DOM tree

and write it out as text. That’s called serialization,

and it’s not an easy task.

And there’s the problem!

Hmm... that is starting to sound like a lot

of work. But I guess I could just create

XML as text, and send that, right?

After all the work you’ve done to learn how to

use the DOM, it seems sort of silly to go back

to text, doesn’t it? In fact, it’s pretty easy to

make a mistake writing XML manually; that’s

part of why the DOM is so powerful. It helps

keep you from making mistakes in your XML

document’s structure.

And besides, what exactly are you getting

out of all the extra work involved in sending

XML to a server instead of name/value pairs

using plain old text?

Why would you do that?

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Chapter 6

You are back? I zought you were

cured! What zeems to be the problem?

Server: I nally found a way to ...