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Main Page

getTempCallback

var oProxyCreateCallback = {

onLoad: function(oCreatedProxy) {

oProxy = oCreatedProxy;

oProxy.setListener(oGetTempCallback);

onError: function(sError) {

alert(sError);

}

};

The callback object for operations is called

oGetTempCallback

, and looks like this:

var oGetTempCallback = {

getTempCallback: function (iDegrees) {

alert(“It is currently “ + iDegrees + “ degrees in that zip code.”);

}

As you can see, the only method is

getTempCallback()

. Because the Web service simply returns a

number, the first (and only) argument contains a simple number. The argument is named

iDegrees

but, in practice, it doesn’t matter what you name the argument. This method is called as soon as

getTemp

returns a value and displays the temperature in a user-friendly message.

Next, a function is needed to create the WSDL proxy. In many cases, it’s best to create the proxy during

the page’s

onload

event handler because of the asynchronous nature of proxy creation, so this example

assigns the function directly to

window.onload

function createProxy() {

try {

var oFactory = new WebServiceProxyFactory();

oFactory.createProxyAsync(sWSDL, sPort, “”, true, oProxyCreateCallback);

} catch (oError) {

alert(oError.message);

}

window.onload = createProxy;

This function creates a

WebServiceProxyFactory

and uses it to create a proxy, assigning the location

of the WSDL file, the port name, and the callback object. It also specifies all methods to be called

asynchronously.

Last is the

callWebService()

function. The function first checks that the proxy has been created before

attempting to make the call. If the proxy has been created, then

getTemp()

is called as a method of the

proxy and the zip code is passed in:

function callWebService() {

if (oProxy) {

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

oProxy.getTemp(sZip);

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