Catalog Client script not working in portal

[ServicenowDev19]

I have written catalog client script on variable set.Whenever i add record in multirow variable set i need to get record count in alert.This script is working when i exceute in TRY IT Scetion. But this script is not working in sp portal when i add row in multi row variable set.

I am geeting the error--Error There is a JavaScript error in your browser console 

Script:

function onSubmit() {

var mrvsStr = parent.g_form.getValue("additional_users");
var mrvsData = JSON.parse(mrvsStr).length + 1;
//var obj = JSON.parse(mrvsStr);
//var length1 = obj.length;
alert('Number of rows in MRV is - ' + mrvsData);
//parent.g_cart.setQuantity(mrvsData);
parent.g_form.setValue('price',mrvsData);

return true;

Please help me why this script is not working in portal.

}

[Anil Lande · Accepted solution]

Hi,

You have to put below line in separate onLoad client script created on catalog Item (Not in variable set client script)

this.my_g_form=g_form;

and use the script provided by me in onSubmit client script for portal:

[ServicenowDev19]

I have written same as your script but then i am getting length as 1 only and it is not setting in price feild.