filtro gridview e dropdownlist

[manesco]

salve a tutti sto cercando di filtrare i dati di un gridview tramite una dropdownlist
il codice è il seguente:

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
DataSourceID="SqlDataSource1" Height="332px" Width="450px">
<Columns>
<asp:BoundField DataField="datoUno" HeaderText="datoUno"
SortExpression="datoUno" />
<asp:BoundField DataField="datoDue" HeaderText="datoDue"
SortExpression="datoDue" />
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server"
ConnectionString="<%$ ConnectionStrings:ConnectionString %>"

SelectCommand="SELECT [datoUno], [datoDue] FROM [uno] WHERE ([datoDue] = @datoDue)">
<SelectParameters>
<asp:ControlParameter ControlID="DropDownList1" Name="datoDue"
PropertyName="SelectedValue" Type="String" />
</SelectParameters>
</asp:SqlDataSource>
<aspropDownList ID="DropDownList1" runat="server" AutoPostBack="True"
Height="24px" Width="225px">
<asp:ListItem>si</asp:ListItem>
<asp:ListItem>no</asp:ListItem>
<asp:ListItem Selected="True">tutte</asp:ListItem>
</aspropDownList>

il problema è che vorrei che quando la dropdownlist si trova su tutte venissero visualizzati tutti i dati, sia dato1 che dato2
come posso fare?

[manesco]

alla fine ho risolto in questo modo:

<aspropDownList ID="DropDownList1" runat="server" AutoPostBack="True"
Height="24px" Width="225px">
<asp:ListItem>si</asp:ListItem>
<asp:ListItem>no</asp:ListItem>
<asp:ListItem value="%">all</asp:ListItem>
</aspropDownList>

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
DataSourceID="SqlDataSource1" Height="332px" Width="450px">
<Columns>
<asp:BoundField DataField="datoUno" HeaderText="datoUno"
SortExpression="datoUno" />
<asp:BoundField DataField="datoDue" HeaderText="datoDue"
SortExpression="datoDue" />
</Columns>
</asp:GridView>

<asp:SqlDataSource ID="SqlDataSource1" runat="server"
ConnectionString="<%$ ConnectionStrings:ConnectionString %>"

SelectCommand="SELECT [datoUno], [datoDue] FROM [uno]"
FilterExpression="[datoDue] like '{0}%'" >
<FilterParameters>
<asp:ControlParameter ControlID="DropDownList1" Name="datoDue"
PropertyName="SelectedValue" Type="String" />

</FilterParameters>
</asp:SqlDataSource>

[djciko]

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