SqlDataSource onSelected 事件未触发

Question

I have an SqlDataSource control with a selectcommand that doesn't fire onselected event (while another one, very similar, fires it). The one that doesn't fire:

<asp:SqlDataSource ID="CommunicationSQLDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:aspnet-WebApplication6-20131007103938ConnectionString1 %>" 
    SelectCommand="SELECT * FROM tCommunication" OnSelected="CommunicationSQLDataSource_Selected">
     <SelectParameters>
        <asp:Parameter Type="String" Name="ProjectID"></asp:Parameter>
    </SelectParameters>
</asp:SqlDataSource>

(The one that fires, just for reference)

<asp:SqlDataSource ID="DetailsSQLDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:aspnet-WebApplication6-20131007103938ConnectionString1 %>"
    SelectCommand="SELECT [ProjectID], ..." OnSelected="DetailsSQLDataSource_Selected">
    <SelectParameters>
        <asp:Parameter Name="ProjectID" Type="Object" />
    </SelectParameters>
</asp:SqlDataSource>

What I see is that the debugger doesn't reach the block of CommunicationSQLDataSource_Selected even though it is referenced in the control.

Answer 1

be sure you Use it in Form tag or asp:Content ..upon which Environment used

<form id="form1" runat="server">
<asp:SqlDataSource ID="DetailsSQLDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:aspnet-WebApplication6-20131007103938ConnectionString1 %>"
    SelectCommand="SELECT [ProjectID], ..." OnSelected="DetailsSQLDataSource_Selected">
    <SelectParameters>
        <asp:Parameter Name="ProjectID" Type="Object" />
    </SelectParameters>
</asp:SqlDataSource>
  </form>

Answer 2

I solved it. I clicked config. data source, and walked through the wizard without changing anything. Thanks for all.

Answer 3

将 CancelSelectOnNullParameter 属性设置为 false