If I fully define a gridview and its associated datasource in the aspx file, I have no problem getting the grid to autosort.
When I move the much of the definition of the grid and datasource to codebehind to be generated dynamically (i.e. to use a single gridview on a page for several purposes depending on what the user requests), auto sort appears to happen after clicking
a sort link, but I wind up with an empty grid.
The followng is defined in my aspx:
<asp:GridView ID="grdRoster" runat="server" AllowSorting="True" EnableViewState="True">
<RowStyle CssClass="rowodd" />
<AlternatingRowStyle CssClass="roweven" />
</asp:GridView>
<br />
<asp:sqldatasource id="ds" runat=server EnableViewState="True"/>
In my codebehind sub that populates the gridview I:
1. create a sql statement string
2. set datasource parameters:
With ds
.ConnectionString = getConnectionString()
.SelectCommand = sql
.DataSourceMode = SqlDataSourceMode.DataSet
End With
3. build out my gridView columns (including sort expressions) based on a list (fieldList) of display fields
4. set and bind the gridView, and make it visible:
With grdRoster
.DataSourceID = ds.ID.ToString
.EnableViewState = True
.AllowSorting = True
If fieldList.Trim = "" Then
.AutoGenerateColumns = True
Else
.AutoGenerateColumns = False
End If
.DataBind()
End With
grdRoster.Visible = True
So far so good. The gridView displays the data in the sort order specified in my starting sql statement.
However, when I click the sort button, the result is an empty gridview. As I trace the request, the gridview.Sorting method shows the correct number of rows in the sender and the expected sorting parameters in the event arguments (e). By the
time I get to the gridview.preRendering and Unload methods, the gridview has 0 rows. Note that the gridview data survives other page postbacks generated by controls outside of the gridview, just not the sort link postback.
If I subsequently run the sub that builds the gridview in the first place, it will be sorted by the last sortlink click I made. What I am left with is having to rerun this sub from the gridview.Sorting method to get my data back in the gridview.
This gets my page to where I want it to be with minimal code, but my understanding was that this should have happened without a subsequent need to call a routine that rebinds the gridview to the datasource.
Any help or advice appreciated! I have only found one reference to this issue, and every tutorial or example I have seen has both the datasource and gridview fully defined on the ASPX page rather than in code-behind.
