An Introduction to Ajax (with JSON) - JavaScript by Example - page 802

Table 18.1 XMLHttpRequest Properties and Event Handlers

XMLHttpRequest Property Value

status The HTTP status code of the request response; for example,

200 or 404.

statusText Returns the HTTP status code from server response as a

string us as OK or Not Found.

readyState A number representing the current state of the object (see

Table 18.3).

responseText Returns a string value of unparsed text as a response from

the server.

responseXML Returns response parsed into a DOM if Content-type is

text/xml. Used to get multiple values.

onreadystatechange The event handler that is called when the readyState

changes.

onerror Mozilla event handler that is called when an error happens

during a request.

onprogress Mozilla event handler called as content is loaded.

onload Mozilla event handler called when the document is finished

loading.

Table 18.2 XMLHttpRequest Methods

XMLHttpRequest Method What It Does

abort() Cancels the request.

getAllResponseHeaders() Returns a string of all the HTTP headers separated by a

newline.

getResponseHeader(“server”) Returns the value of a specific HTTP header; for example,

“Server” or “Last-Modified”.

open() Initializes the XMLHttpRequest object with GET or POST,

URL, and so on.

send() Sends the request.

setRequestHeader() Adds a key/value pair to add to the header that will be sent

to the server.