Question

My SortedAscendingHeaderStyle and SortedDescendingHeaderStyle is not working at all

<asp:GridView ID="grdProducts" runat="server" CssClass="grid" AllowPaging="True" AllowSorting="True" PageSize="100" EmptyDataText="No data to show"
              onrowdatabound="grdProducts_RowDataBound"  onrowediting="grdProducts_RowEditing" onsorting="grdProducts_Sorting" AutoGenerateEditButton="True">
  <AlternatingRowStyle CssClass="even" />
  <SortedAscendingHeaderStyle ForeColor="White" CssClass="sorted" />
  <SortedDescendingHeaderStyle CssClass="sorted desc" />
</asp:GridView>

Rows are sorted correctly when headers are clicked, but when I inspect the header using FireBug, it only shows: (this is when sorted ascending)

<th scope="col">
  <a href="javascript:__doPostBack('ctl00$body$ctl00$grdProducts','Sort$Namekey')">Namekey</a>
</th>

ForeColor and CssClass are not set at all.

Anyone has any idea what I am doing wrong?

EDIT: My C# code behind

  protected void grdProducts_Sorting(object sender, GridViewSortEventArgs e)
  {
    if ((string)ViewState["SortColumn"] == e.SortExpression)
      ViewState["SortDirection"] = ((string)ViewState["SortDirection"] == "") ? " DESC" : "";
    else
    {
      ViewState["SortColumn"] = e.SortExpression;
      ViewState["SortDirection"] = "";
    }
  }

  protected override void OnPreRender(EventArgs e)
  {
    BindGrid();
    base.OnPreRender(e);
  }

  private void BindGrid()
  {
    string query = "SELECT ... ORDER BY " + ViewState["SortColumn"] + ViewState["SortDirection"];

    DataTable dt = SqlFunctions.Select(query);
    grdProducts.DataSource = dt;
    grdProducts.DataBind();
  }

Answer 1

I’m not sure if SortedDescendingHeaderStyle works without code if you’re not using an asp:SQLDataSource as your GridView data source. But a little coding can get you there.

You need to apply the CSS style manually to the header cell. You can do it in the Sorting event.

protected void grdProducts_Sorting(object sender, GridViewSortEventArgs e)
{
   if ((string)ViewState["SortColumn"] == e.SortExpression)
   {
      ViewState["SortDirection"] = ((string)ViewState["SortDirection"] == "") ? " DESC" : "";
      grdProducts.HeaderRow.Cells[GetColumnIndex( e.SortExpression )].CssClass = "AscendingHeaderStyle";
   }
   else
   {
      ViewState["SortColumn"] = e.SortExpression;
      ViewState["SortDirection"] = "";
      grdProducts.HeaderRow.Cells[GetColumnIndex( e.SortExpression )].CssClass = "DescendingHeaderStyle";
   }
   BindGrid();
}




private int GetColumnIndex( string SortExpression )
{
    int i = 0;
    foreach( DataControlField c in gvwCustomers.Columns )
    {
        if( c.SortExpression == SortExpression )
            break;
        i++;
    }
    return i;
}