Getting the DataSource of the Caller Form

I was working on scenario in which there another form is open from one form and I need to get the datasource from the caller form in my new form.

The code to get the datasource of the caller form is:

CustTable = custTable;

if(element.args().record().TableId == tablenum(CustTable))
{
    custTable = element.args().record();
}


Thanks

Muhammad Zahid.