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SOAP error

Once again, the first function is named

callWebService()

. The first step must be a request for

enhanced privileges as described previously. If the privileges aren’t given, there’s no point in the func-

tion continuing, so it returns. If the privileges are enabled, then the zip code is retrieved and placed in a

SOAPParameter

array. Lastly, the SOAP call is created and made asynchronously:

function callWebService() {

try {

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

} catch (e) {

alert(e);

return false;

}

var sZip = document.getElementById(“txtZip”).value;

var arrParams = new Array;

arrParams[0] = new SOAPParameter(sZip, “zipcode”);

var oSoapCall = new SOAPCall();

oSoapCall.transportURI = sURL;

oSoapCall.encode(0, “getTemp”, sTargetNamespace, 0, null,

arrParams.length, arrParams);

oSoapCall.asyncInvoke(onWebServiceResult);

}

Next, the

onWebServiceResult()

function handles the response. Most of the function is dedicated to

determining if an error occurred during the Web service call:

function onWebServiceResult(oResponse,oSoapCall,iError) {

if (iError != 0) {

alert(“An unspecified error occurred.”);

} else if (oResponse.fault != null) {

alert(“An error occurred (code=” + oResponse.fault.faultCode

+ “, string=” + oResponse.fault.faultString + “)”);

} else {

var oParams = oResponse.getParameters(false, {});

alert(“It is currently “ + oParams[0].element.firstChild.nodeValue

+ “ degrees in that zip code.”);

}

The first step in this function is to check the error code

iError

. If it’s not equal to

, that means there

isn’t a response to evaluate, so an error message is displayed. If the error code is

, the next step is to

determine that there wasn’t a SOAP error. This ensures that the

fault

property is

null

(if it’s not, a

detailed error message is displayed).

When the two other conditions fail, the response must be valid. So, the value of the first parameter is

displayed in a user-friendly message.

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Web Services

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