I have two different options in JavaScript

Option 1:

        var _option = {
            "displayLength": _length,
            "order": [[ _order, ""+_sort+"" ]],
            "paging": _pages,
            "info": _info,
            "searching": _search
        }

Option 2:

        var _button_option = {
            dom: 'Bfrtip',
            buttons: [
                'copy',
                'excel',
                'print'
            ]
        }

I want to merge two option values to the one values

Result like this:

        var _option = {
            "displayLength": _length,
            "order": [[ _order, ""+_sort+"" ]],
            "paging": _pages,
            "info": _info,
            "searching": _search,
            dom: 'Bfrtip',
            buttons: [
                'copy',
                'excel',
                'print'
            ]
        }

How to merge two options in JavaScript?