当Girdview的数据源为空时，也显示表头

 protected void GridViewDatabind()
    {
        DataTable dt = employer.GetPost();
        if (dt!= null)
        {
            GridView1.ShowHeader = true;
            if (dt.Rows.Count == 0)
            {

                dt.Rows.Add(dt.NewRow());
                GridView1.DataSource = dt;
                GridView1.DataBind();
                GridView1.Rows[0].Visible = false;
                GridView1.Rows[0].Cells.Clear();

            }
            else
            {
                GridView1.DataSource = dt;
                GridView1.DataBind();
            }

        }

    }