Attaching the WebService Behavior
In order to call remote methods from Web Services, you need to use the WebService behavior. The WebService behavior is implemented as an HTML Component (HTC), so it can be used in Microsoft Internet Explorer 5 and later versions. The WebService behavior communicates with Web Services over HTTP using Simple Object Access Protocol (SOAP).
The first step in using the WebService behavior is to attach it to an element using the STYLE attribute. It is also necessary to set the ID attribute so that this element can be easily referenced in script. You can attach the WebService behavior to various types of elements. Here is an example that shows how to attach it to a DIV element:
<DIV ID="webServiceCallerDiv"
STYLE="behavior:url(webservice.htc)"></DIV>
And here is an example that shows how to attach it to a BODY element:
<BODY ID="webServiceCallerBody"
STYLE="behavior:url(webservice.htc)"></BODY>
The behavior can also be applied using other variations of Cascading Style Sheets (CSS) syntax.
To begin working with the WebService behavior, download the WebService HTC file and copy it to the same directory as the Web page that uses the behavior. By placing the WebService HTC file in the same directory as your HTML page that calls it, you avoid any DHTML behavior-related cross-domain security issues.
The behavior webservice.htc is the cornerstone for enabling Web service calls from JavaScript. This behavior is rather complicated. It consists of over 2000 lines, divided among more than 75 functions. In general, most of the interface to this behavior is done via its public properties, events, and methods, as defined in the PUBLIC:COMPONENT element:
<PUBLIC:COMPONENT ID=_webservice Name="WEBSERVICE" >
<PUBLIC:PROPERTY NAME="version"
VALUE="Microsoft WebService Behavior 1.0.1.810" />
<PUBLIC:PROPERTY NAME="showProgress" VALUE=false />
<PUBLIC:METHOD NAME="useService"/>
<PUBLIC:METHOD NAME="createCallOptions"/>
<PUBLIC:METHOD NAME="createUseOptions"/>
<PUBLIC:METHOD NAME="invokeNext"/>
<PUBLIC:METHOD NAME="callService"/>
<PUBLIC:EVENT ID="eventResult" NAME="onresult"/>
<PUBLIC:EVENT ID="eventService"
NAME="onserviceavailable"/>
</PUBLIC:COMPONENT>
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