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Web service support

function WebService() {

this.action = “”;

this.url = “”;

}

WebService.prototype.buildRequest = function () {

return “”;

};

WebService.prototype.handleResponse = function (sSOAP) {

};

WebService.prototype.send = function () {

if (isMoz) {

try {

netscape.security.PrivilegeManager.enablePrivilege(“UniversalBrowserRead”);

} catch (oError) {

alert(oError);

return false;

}

var oRequest = new XMLHttpRequest;

oRequest.open(“post”, this.url, false);

oRequest.setRequestHeader(“Content-Type”, “text/xml”);

oRequest.setRequestHeader(“SOAPAction”, this.action);

oRequest.send(this.buildRequest());

if (oRequest.status == 200) {

return this.handleResponse(oRequest.responseText);

} else {

throw new Error(“Request did not complete, code “ + oRequest.status);

}

};

The

WebService

object is the basis of cross-browser Web service support. It has two properties: the URL

for the SOAP request (

url

) and the SOAP action (

action

). Both properties are initialized to

null

; sub-

classes fill these in as needed. The

buildRequest()

method is intended to build the SOAP message

string; but in this case, it just returns an empty string. The

handleResponse()

method receives the

SOAP message from the response and returns the appropriate value.

The

send()

method does the heavy lifting for this functionality. First, if the browser is Mozilla, you

must request the

UniversalBrowserRead

privilege. Then, an

XMLHttpRequest

object is created

(remember, this code uses the wrapper for IE), and the SOAP request is built up. This request includes

opening a request to the specified URL, setting the content type to

“text/xml”

and setting the SOAP

action. Then, the

buildRequest()

method is called to get the SOAP message and send it using the

XMLHttpRequest

’s

send()

method.

Lastly, if the request returns a status of 200, the text returned is interpreted by the

handleResponse()

and that value is returned. Otherwise, an error is thrown. The intent is to allow you to use a

WebService

object like this:

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