asp.net trigger for a checkbox control
<p>Hi All i am using the below code and wanted to make a button visible and invisible based on checkbox status. I am using the trigger to call a event where i will write code to make that button visible or invisible. If i use the below code i get an error like "System.InvalidOperationException: A control with ID 'chkDelete' could not be found for the trigger in UpdatePanel 'UpdatePanel1'." Please help me.</p>

<pre><code>&lt;asp:ScriptManager ID="ScriptManager1" runat="server" /&gt; 
     &lt;asp:UpdatePanel ID="UpdatePanel1" runat="server" ChildrenAsTriggers ="false"&gt; 
     &lt;ContentTemplate&gt; 
             &lt;asp:GridView ID="gvEventMechanic" runat="server" AutoGenerateColumns="False" PageSize="5" 
                        GridLines="None" AllowSorting="true" BorderWidth="1" 
                        EnableViewState="true" AllowPaging="true"&gt;       
            &lt;Columns&gt; 
                &lt;asp:TemplateField&gt;                     
                    &lt;HeaderTemplate&gt; 
                        Disable 
                        &lt;/HeaderTemplate&gt; 
                    &lt;ItemStyle HorizontalAlign="Center" /&gt; 
                    &lt;ItemTemplate&gt;                            
                        &lt;asp:CheckBox ID="chkDelete" runat="server" AutoPostBack="true" &gt;&lt;/asp:CheckBox&gt; 
                    &lt;/ItemTemplate&gt; 
                &lt;/asp:TemplateField&gt;                    
            &lt;/Columns&gt;                 
        &lt;/asp:GridView&gt; 
        &lt;/ContentTemplate&gt;   
         &lt;Triggers&gt; 
                &lt;asp:AsyncPostBackTrigger ControlID="chkDelete" EventName="CheckBoxEventChanged" /&gt; 
            &lt;/Triggers&gt;                    
        &lt;/asp:UpdatePanel&gt;
</code></pre>
