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The HttpRequest object provides client-side communication with a
server.
Examples
readyState
How to return the state of the document. This property changes
as the document is being loaded.
responseText
How to return the request as a string.
status
How to return the status of the operation, as a code.
statusText
How to return the status of the operation, as a string.
The HttpRequest object
With the httpRequest object you can send a request from the
client to the server.
If you are using JavaScript in IE 5.0, you can create the
httpRequest object with the following code:
var xmlHTTP = new ActiveXObject("Microsoft.XMLHTTP")
If you are using VBScript you create the httpRequest object with
the following code:
set xmlHTTP = CreateObject("Microsoft.XMLHTTP")
The httpRequest object is not a part of the W3C DOM standard.
Get XML
How to get an xml file from the server using the httpRequest
object.
var xmlHttp = new ActiveXObject("Microsoft.XMLHTTP")
xmlHttp.open("GET", "note.xml", false)
xmlHttp.send()
xmlDoc=xmlHttp.responseText
Send XML
You can also send an xml document to an ASP page on the server,
analyze the request, and send back the result.
var xmlHttp = new ActiveXObject("Microsoft.XMLHTTP")
xmlHttp.open("POST", "demo_dom_http.asp", false)
xmlHttp.send(xmlDoc)
document.write(xmlHttp.responseText)
The ASP page, written in VBScript:
set xmldoc = Server.CreateObject("Microsoft.XMLDOM")
xmldoc.async=false
xmldoc.load(request)
for each x in xmldoc.documentElement.childNodes
if x.NodeName = "to" then
name=x.text
next
response.write(name)
You send the result back to the client using the response.write
property.
Important Note
At the moment, the Microsoft XMLHTTP object can only be run in
the BROWSER.
SERVER code that attempts to use the XMLHTTP to communicate with
other Web servers, may function incorrectly or perform poorly.
This is a bug in the HTTPRequest object.
The rumor is that Microsoft will have this bug fixed in an
upcoming release of the XML Library. In the meantime, you may
have to use a commercially available ASPHTTP component.
The httpRequest Properties
Property Description
readyState Returns the state of the document
responseBody Returns the response as an array of unsigned bytes
responseStream Returns the response as an IStream
responseText Returns the response as a string
responseXML Returns the response as an xml document
status Returns the status code as a number
statusText Returns the status as a string
The httpRequest Methods
Property Description
abort() Cancel the current http request
getAllResponseHeaders() Returns the value of the http headers
getResponseHeader(headerName) Returns the value of one specified
http header
open(method, url, async, userid, password) Opens http request,
and specifies the informationsend() Send the http request to the
server
setRequestHeader(headerName,headerValue) Specifies the name of a
http header
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