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JavaScript execution

When this method is called, the component downloads the WSDL file and uses it to create JavaScript

objects and methods to access the Web service. This functionality is available through an object identi-

fied by the friendly name specified in the

useService()

method:

var oSpecificService = oService.FriendlyName;

This object has a method,

callService()

, that makes the actual request to the server. The method

accepts a function name to call and any number of parameters to pass to that function. When executed,

callService()

returns a call ID that is necessary when you want to retrieve a value from the result.

The format for this method call is as follows:

iCallID = oService.FriendlyName.callService(sFuncName, sParam0, sParam1..sParamN);

The Web service call is then made asynchronously, so JavaScript execution won’t stop and wait for the

response from the server. Instead, you must use the

onresult

event handler to handle the response. You

can either assign the event handler right in the HTML or by using JavaScript. Using HTML, just treat

onresult

as if it were any other event handler:

To assign the event handler using JavaScript, assign the function directly to the

onresult

property:

oService.onresult = function () {

alert(“Done”);

};

When the

result

event is fired, it creates an

event

object with a special property called

result

. This

property contains an object with all the details about the response. The properties of

result

are listed in

the following table:

Property Name

Data Type

Description

error

Boolean

True if an error occurred during the call

errorDetail

Object

An object that contains all the information about an

error, if one occurs. The two properties of interest are

the code that returns the error code and the string that

returns a human-readable error message.

Number

The call ID created by

callService()

raw

String

The raw SOAP code being sent back from the server

SOAPHeader

Array

An array of headers used for the call

value

Variant

The value returned by the call. This may be a simple data

type, like a number or string, or it could be an object.

So how do you use this object? Here’s a simple example:

var iCallID = -1;

oService.onresult = function () {

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