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Web Services in Internet Explorer

The pertinent information (highlighted previously) from this file is the following:

The only operation is called

getTemp

The SOAP action for

getTemp

is “” (an empty string).

The target namespace for the input to

getTemp

urn:xmethods-Temperature

The name of the port is

TemperaturePort

The service location is

http://services.xmethods.net:80/soap/servlet/rpcrouter

Depending on the type of consumer used to access Web services, you may need to know some or all the

previous information.

Web Services in Internet Explorer

The folks over at Microsoft were kind enough to create an HTML component (also called a behavior)

that hides a lot of the ugly details from developers who wish to consume Web services. An HTML com-

ponent is essentially a COM component defined using XML and JavaScript. HTML components can

have properties, methods, and support custom events, making them ideal for creating functionality that

doesn’t exist in the browser by default. The downside is that only Internet Explorer supports HTML

components, and thus Microsoft’s

WebService

component does not work in other browsers. The

WebService

component is available for free from Microsoft’s Web site (

http://msdn.microsoft.com/

library/default.asp?url=/workshop/author/webservice/webservice.asp

Using the WebService component

After the

webservice.htc

file is downloaded, place it in the directory with your JavaScript files. You

can then access the functionality by applying it to an HTML element. To do this, use the

style

attribute

and the custom

behavior

CSS attribute:

After doing this, the HTML element takes on all the properties, methods, and events of the

WebService

component. To use the component as a JavaScript object, just assign an ID to the element:

Then use the

document.getElementById()

method to retrieve a reference:

var oService = document.getElementById(“service”);

Next, you need to specify a Web service to use by calling

useService()

. The

useService()

method

accepts two parameters: the WSDL file describing the service and a friendly name for the service. A typi-

cal call looks like this:

oService.useService(sUrl, “FriendlyName”);

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Web Services

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