How to access global variable in catalog client scripts?

[John_123_Snow]

I'm trying to create a global variable in a Catalog Client Script, available for all other client scripts to access:

var globalVar = '';

function onLoad() {

	var ajax = new GlideAjax('TestScriptInclude');
	ajax.addParam('sysparm_name', 'returnProperty');
	ajax.getXMLAnswer(function(answer) {
		globalVar = answer;
	});

}

This onLoad client script calls to the server and gets an array of values that I need for other client scripts to use with onChange and onSubmit.

How do I set this up correctly and access it in my other catalog client scripts?

[Vedo]

Hi, I have tried as described above but in the onChange function the global variable is not defined. I have follwoing error message: 

ReferenceError: globalVarTest is not defined

Isolate script on all script is unchecked