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Chapter 5
HTML Form PHP Script CallbackSend Order
You have to set the content type for your POST data before you send the request.
Then, when the request is sent, the server will get the request URL, the POST data,
and the type of data it should expect. Anytime you need to tell a server something
about a request, you’ll use a request header.
Let’s see how we can set a request header for the Break Neck request:
Setting the Content Type
function submitOrder() {
var phone = document.getElementById(“phone”).value;
var address = document.getElementById(“address”).value;
var order = document.getElementById(“order”).value;
var url = “placeOrder.php”;
request.open(“POST”, url, true);
request.onreadystatechange = showConrmation;
request.setRequestHeader(“Content-Type”,
“application/x-www-form-urlencoded”);
request.send(“phone=” + escape(phone) +
“&address=” + escape(address) +
“&order=” + escape(order));
}
setRequestHeader()
allows you to add
information to the
request, usually
intended for use by
the server.
“Content-Type” is the
name of the header...
...and this is the value for
that request header.
This tells the server the data is encoded like
it would be in a request URL, just as if the
data came as part of a GET request.
Q:
So a request header is sent to the server along with
the request?
a: Yes. Any request headers are part of the request. In fact,
the web browser sets some ...