How to find the date difference from 2 fields.

Hi,

you need to do a range check. This sample from an old draft of mine contains a separate class for the Data Range calculation that may work for your use case too:

https://github.com/AngelaIp/aras-pm-resource-mgmt/blob/master/Import/pmResourceMgmt/Import/Method/BPL_PM_Resource_checkDates.xml

If you skip the activity stuff, you should be able to reuse where ever you want with this call:

var body = "<start_date_>" + dateStart + "</start_date_>" +
"<end_date_>" + dateEnd + "</end_date_>";

var result = aras.applyMethod("MyMethodname",body);