datable添加列实现了.但是怎么把数据绑定到这个列中?????

            employeeByIsHoliday = _presenter.GetAllMessageIsHoliday("%", "%", _fromDateTimePicker.Text.ToString(), _endDateTimePicker.Text.ToString());

            string workAllDays = Convert.ToString(employeeByIsHoliday.Rows.Count);

            //employeeByIsHoliday.Count是上班天数
            DataTable dt = new DataTable();
            dt.Columns.Add("WorkAllDays", typeof(string));

            dataGridView1.DataSource = dt;

我这里是想把employeeByIsHoliday 的COUNT的数据绑定到新添加的列中.该怎么写???