Head Rush Ajax

you’re on your way 4

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ajax requests

Next we need to tell the browser what to do when it gets a response from the server. Remember,

the browser will run the function we tell it about every time the ready state changes.

Giving instructions to the browser

function getCustomerInfo() {

var phone = document.getElementById(“phone”).value;

var url = “lookupCustomer.php?phone=” + escape(phone);

request.open(“GET”, url, true);

request.onreadystatechange = updatePage;

request.send(null);

}

Here’s the name of the function

that the browser should run

whenever the ready state of the

request object changes.

Be sure you set the

onreadystatechange property before

calling send(), so the browser knows

what to do when it gets a response.

Now that you’ve got the request URL gured out, you can initialize a connection using

the request object’s open() method. You should remember how the open() method

works from Chapter 1. Below is the line of JavaScript that initializes a connection, with

each parameter you give to open() on a separate line. In each blank, write in what the

parameter for that line tells the request object to do.

______________________________________________

______________________________________________

______________________________________________

request.open(

“GET”,

url,

true

);

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Chapter ...