how to create a dynamic gridview header in asp.net

protected void gvEmployee_RowCreated(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.Header)
{
GridViewRow HeaderRow = new GridViewRow(1, 0, DataControlRowType.Header, DataControlRowState.Insert);

    TableCell HeaderCell2 = new TableCell();
    HeaderCell2.Text = "Personal Details";
    HeaderCell2.ColumnSpan = 2;
    HeaderRow.Cells.Add(HeaderCell2);

    HeaderCell2 = new TableCell();
    HeaderCell2.Text = "Location";
    HeaderCell2.ColumnSpan = 2;
    HeaderRow.Cells.Add(HeaderCell2);

    HeaderCell2 = new TableCell();
    HeaderCell2.Text = "Office details";
    HeaderCell2.ColumnSpan = 2;
    HeaderRow.Cells.Add(HeaderCell2);

    gvEmployee.Controls[0].Controls.AddAt(0, HeaderRow);

    GridViewRow HeaderRow1 = new GridViewRow(0, 0, DataControlRowType.Header, DataControlRowState.Insert);

    TableCell HeaderCell = new TableCell();
    HeaderCell.Text = "Employee-ID";
    HeaderRow1.Cells.Add(HeaderCell);

    HeaderCell = new TableCell();
    HeaderCell.Text = "Name";
    HeaderRow1.Cells.Add(HeaderCell);

    HeaderCell = new TableCell();
    HeaderCell.Text = "City";
    HeaderRow1.Cells.Add(HeaderCell);

    HeaderCell = new TableCell();
    HeaderCell.Text = "Country";
    HeaderRow1.Cells.Add(HeaderCell);

    HeaderCell = new TableCell();
    HeaderCell.Text = "Designation";
    HeaderRow1.Cells.Add(HeaderCell);

    HeaderCell = new TableCell();
    HeaderCell.Text = "Joining date";
    HeaderRow1.Cells.Add(HeaderCell);

    HeaderRow.Attributes.Add("class", "header");
    HeaderRow1.Attributes.Add("class", "header");
    gvEmployee.Controls[0].Controls.AddAt(1, HeaderRow1);
}

}