How to get webgrid column values for each row on controller side in MVC

how to get webgrid column values for each row on controller side in mvc or if want to get particular row and column value.

var exceldata = Db.stus.ToList();
            WebGrid grid = new WebGrid(source: exceldata, canPage: false, canSort: false);
            var gridData = grid.GetHtml(
            columns: grid.Columns(
                            grid.Column("stu_id", "Id"),
                            grid.Column("Stu_name", "Name"),
                            grid.Column("class", "Class"),
                            grid.Column("roll", "Roll"),
                            grid.Column("email", "Email"),
                            grid.Column("phone", "Phone")
                            )).ToString();
            int columns = gridData.Length;
foreach(var item in gridData)
{
int id=????
string class=???
string name=???
string email=???
}