If statement to work if value is contain in an array (client script)

[Jacob23]

Hi,

I wonder if you could assist with my client script, let me explain the use case. 

I have a request where you select an application, this application field is a refence field to our cmdb. Once you select the application you are then able to select the roles associated to this application, this field is a list collector and currently you can select all of the roles associated to the app.

We now have a requirement for 1 app to be locked down so only 1 role can be selected. This was done with a client script which I will paste below. This has been developed to work specifically for the 1 app, but I would like to make this a re-usable process. 

function onChange(control, oldValue, newValue, isLoading) {
	if (isLoading || newValue == '') {
		return;
	}

	var application = g_form.getValue('appl');

	if (application == 'sys id of app') {
		var maxOptions = 1;
		var selectedRoles = g_form.getValue('role_select');
		var selectedOptions = selectedRoles.split(',');

		if (selectedOptions.length > maxOptions) {
			//Remove the last item
			g_form.clearValue('role_select');
			g_form.addErrorMessage('You cannot select more than ' + maxOptions + ' role for this application.');
		}
	}
}

This code above works but I want to make it expandable for other apps. I would like to be able to come into this script and add to a variable the sys ID of any app I want to add. What would be the best way to do this?

I was initially thinking of creating an array then have the IF statement look to see if the array contains the app found in the g_form.getValue(). This has proven difficult. I have been trying indexOf() and includes(), either I have done it wrong or these are not working for what I need. 

[Claude DAmico · Accepted solution]

I'm thinking something like this where you have an array and just check if the current application selected is in that array.

function onChange(control, oldValue, newValue, isLoading) {
	if (isLoading || newValue == '') {
		return;
	}

	var application = g_form.getValue('appl');
	var controlApps = ['sys_id','sys_id','sys_id'];

	if (controlApps.indexOf(application) != -1) {
		var maxOptions = 1;
		var selectedRoles = g_form.getValue('role_select');
		var selectedOptions = selectedRoles.split(',');

		if (selectedOptions.length > maxOptions) {
			//Remove the last item
			g_form.clearValue('role_select');
			g_form.addErrorMessage('You cannot select more than ' + maxOptions + ' role for this application.');
		}
	}
}

[Jacob23]

Legend this worked. I had the same a part from the != -1, not having this was having the IF statement run as true if the start of the sys ID was the same. Are you able to explain what the -1 does?

[Claude DAmico]

Of course! The .indexOf() part checks for the index of the value in the string/array/etc. If it doesn't exist, the index is -1. Example:

Array = [0,1,2];

Array.indexOf(0) returns an index of 0, (1) returns 1, (2) returns 2

Array.indexOf(3) returns an index of -1 since it isn't in the array

Thus, Array.indexOf(0) != -1 returns true because the index returned is not -1 meaning it is in the array.

[Jacob23]

Thank you!