When I hard code the values into the updatecommand then the gridview gets updated, but if I just have the parameters the gridview does not get updated.  What could the issue be?

This updates the grid:
UpdateCommand="Update atable set [afield]='test', [bfield]='test' where [id]=@id"
<UpdateParameters>
             <asp:Parameter Name="afield" Type="string" />
             <asp:Parameter Name="bfield" Type="string" />
<asp:Parameter Name="id" Type="Int32"
             </UpdateParameters>

This doesn't:
UpdateCommand="Update atable set [afield]=@afield, [bfield]=@bfield where [id]=@id"

<UpdateParameters>
             <asp:Parameter Name="afield" Type="string" />
             <asp:Parameter Name="bfield" Type="string" />
<asp:Parameter Name="id" Type="Int32"
             </UpdateParameters>

Instead of this  

newbieAl:

<UpdateParameters>
             <asp:Parameter Name="afield" Type="string" />
             <asp:Parameter Name="bfield" Type="string" />
<asp:Parameter Name="id" Type="Int32"
             </UpdateParameters>

Try

<UpdateParameters>
             <asp:Parameter Name="@afield" Type="string" />
             <asp:Parameter Name="@bfield" Type="string" />
<asp:Parameter Name="@id" Type="Int32"
             </UpdateParameters>

 good idea...but that didn't work either.

Your GridView code please.

Here is my Gridview code.  In addition to gridview I have 2 dropdownlists and the filtering logic is on the page_load event one the code behind (VB).
 

 <asp:GridView ID="GridView1" runat="server" AllowPaging="True" AllowSorting="True"
            AutoGenerateColumns="False" BackColor="White" BorderColor="#999999" BorderStyle="None"
            BorderWidth="1px" CellPadding="3" DataKeyNames="ID" DataSourceID="DATA"
            GridLines="Vertical"
        Font-Names="Verdana"
        Font-Size="8pt"
        HeaderStyle-BackColor="#aaaadd" >
        <PagerSettings Position="TopAndBottom"
          FirstPageText="First Page"
          LastPageText="Last Page" 
          Mode="NumericFirstLast" >
     </PagerSettings>
 
            <FooterStyle BackColor="#CCCCCC" ForeColor="Black" />
            <Columns>
                <asp:HyperLinkField DataNavigateUrlFields="ANOTHER_ID" DataNavigateUrlFormatString="test2.aspx?ANOTHER_ID={0}"
                    Text="View Record" />
                <asp:CommandField ShowEditButton="True" />
                <asp:BoundField DataField="ID" HeaderText="ID" InsertVisible="False"
                    ReadOnly="True" SortExpression="ID" />
                <asp:BoundField DataField="AFIELD" HeaderText="AFIELD" SortExpression="AFIELD" />
                <asp:BoundField DataField="BFIELD" HeaderText="BFIELD" SortExpression="BFIELD" />
                <asp:BoundField DataField="CFIELD" HeaderText="CFIELD" SortExpression="CFIELD" ReadOnly="True" />
                <asp:BoundField DataField="DATE" HeaderText="DATE" SortExpression="DATE" ReadOnly="True" />                
            </Columns>
            <RowStyle BackColor="#EEEEEE" ForeColor="Black" />
            <EmptyDataTemplate>
                No Records Found
            </EmptyDataTemplate>
            <SelectedRowStyle BackColor="#008A8C" Font-Bold="True" ForeColor="White" />
            <PagerStyle BackColor="#999999" ForeColor="Black" HorizontalAlign="Center" />
            <HeaderStyle BackColor="#000084" Font-Bold="True" ForeColor="White" />
            <AlternatingRowStyle BackColor="Gainsboro" />
        </asp:GridView>

I have this logic in the page_load:

If Not Page.IsPostBack Then

            GridView1.DataBind()

        End If

        If DropDownList1.SelectedIndex.Equals(0) And DropDownList2.SelectedIndex.Equals(0) Then

            DATA.SelectCommand = ("SELECT * FROM [ATABLE]")

            GridView1.DataBind()

        ElseIf Not DropDownList1.SelectedIndex.Equals(0) And DropDownList2.SelectedIndex.Equals(0) Then

            DATA.SelectCommand = ("SELECT * FROM [ATABLE] where AFIELD = '" & DropDownList1.SelectedValue.ToString & " ' ")

            GridView1.DataBind()

        ElseIf DropDownList1.SelectedIndex.Equals(0) And Not DropDownList2.SelectedIndex.Equals(0) Then

            DATA.SelectCommand = ("SELECT * FROM [ATABLE] where BFIELD = '" & DropDownList2.SelectedValue.ToString & " ' ")

            GridView1.DataBind()

        ElseIf Not DropDownList1.SelectedIndex.Equals(0) And Not DropDownList2.SelectedIndex.Equals(0) Then

            DATA.SelectCommand = ("SELECT * FROM [ATABLE] where AFIELD = '" & DropDownList1.SelectedValue.ToString & " ' and BFIELD = '" & DropDownList2.SelectedValue.ToString & " ' ")

            GridView1.DataBind()

        End If

Once I removed this code, the update worked.  Where should I put this code so that it doesn't interfere with the update? 

 if i take the databind out in page_load then the filtering doesn't work.  If I put the code in the selectindexchanged event then the gridview is not displayed when the page loads.  Also, when I got to edit a filtered record, the page just refreshes and the grid is gone...

 I've found the solution.  I removed the page_load, dropdownlist logic, and added it to the sqldatasource: select command in the aspx page.  It works now.