Question

I am using ASP.NET 4.5 Model Binding to present items in a ListView control with editing.

<asp:ListView ID="Results" runat="server" SelectMethod="SelectClientStatus" DataKeyNames="ID" ItemPlaceholderID="itemPlaceHolder" ItemType="ClientStatus" OnItemCommand="Results_ItemCommand" InsertItemPosition="LastItem" UpdateMethod="UpdateClientStatus" InsertMethod="InsertClientStatus">
    <LayoutTemplate>
        <table>
            <tr>
                <th runat="server">
                    <asp:LinkButton ID="SortByDescription" runat="server" ClientIDMode="Static" CommandName="Sort" CommandArgument="Description" Text="Description" />
                </th>
                <th>Active</th>
                <th></th>
            </tr>
            <asp:PlaceHolder ID="itemPlaceHolder" runat="server" />
        </table>
        <agp:PagerControl runat="server" ID="PagerControl" />
    </LayoutTemplate>
    <ItemTemplate>
        <tr>
            <td>
                <%#: Item.Description%>
            </td>
            <td>
                <%#: Item.IsClientActive %>
            </td>
            <td>
                <asp:LinkButton ID="Edit" runat="server" ClientIDMode="Static" CommandName="Edit" CommandArgument="<%#: Item.ID %>" Text="Edit" />
            </td>
        </tr>
    </ItemTemplate>
</asp:ListView>

When I add my EditItemTemplate, I have a Checkbox and I am trying to bind the Checked property to the model…

<EditItemTemplate>
    <tr>
        <td>
            <asp:TextBox ID="Description" runat="server" Text="<%#: BindItem.Description%>" />
        </td>
        <td>
            <asp:CheckBox ID="IsActive" runat="server" Checked="<%#: BindItem.IsClientActive %>" />
        </td>
        <td>
            <asp:LinkButton ID="Update" runat="server" ClientIDMode="Static"
                CommandName="Update" CommandArgument="<%#: Item.ID %>"
                Text="Update" />
            <asp:LinkButton ID="Cancel" runat="server" ClientIDMode="Static"
                CommandName="Cancel" CommandArgument="<%#: Item.ID %>"
                Text="Cancel" />
        </td>
    </tr>
</EditItemTemplate>

This is where the problem starts, running the page now shows a message of “CS0030: Cannot convert type ‘string’ to ‘bool'”, prompting with the line…

<td>
<asp:CheckBox ID="IsActive" runat="server" Checked="<%#: BindItem.IsClientActive %>" />
</td>

What have I missed? How do I bind the value of IsClientActive to the Checked property of the Checkbox control? It is worth noting that, within the model, the IsClientActive property is defined as a Boolean and not nullable.

Answer 1

My bad; Checked="<%#: BindItem.IsClientActive %>" should have been Checked="<%# BindItem.IsClientActive %>" (note the omission of the colon (:))