The JavaScript code is receiving an "undefined" response from the WebService method, despite expecting a valid return value

One of my WebService's methods is designed to return a boolean:

[WebMethod(EnableSession = true), ScriptMethod(UseHttpGet = true)]
public bool StartMonitoring()
{
    return Schedule.StartMonitoring();
}

The method within the Schedule class looks like this:

public static bool StartMonitoring()
{
    return true;
}

There is also a service call in JavaScript that looks like this:

var success = false;
success = myself.get_Service().StartMonitoring();
alert(success);

However, when the pop-up appears, it displays "undefined" instead of true.

What could be causing this issue?

Answer №1

It seems like you may be using an AJAX proxy technology where a callback function is required. Your JavaScript code should be structured in this way:

myself.get_Service().StartMonitoring(myCustomCallback);

function myCustomCallback(response)
{
     alert(response);
}

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