jqGrid - How to put a specify page number

I want to make the following : 1. I have the following formatter function:

    function ActionDescriptionFormatter(cellval, opts, rwdat, _act) {
        var str = "<a border='0' style='text-decoration: none;' href='/Admin/IdeaDescription?id=" + cellval + "' title='Description'><img src='/images/aico_descr.png' alt='Description' border='0' 开发者_StackOverflow中文版/></a>";
        return str;
    }

I want to add also current pagenumber to url.

1. I want to set page of grid if It's passed via url

How to do it?