<dx:ASPxCheckBox ID="chkDisabled" runat="server" Text="Disable selection checkboxes"
    AutoPostBack="true" />

<dx:ASPxCardView ID="ASPxCardView1" runat="server" DataSourceID="AccessDataSource1" KeyFieldName="CustomerID" OnCommandButtonInitialize="ASPxCardView1_CommandButtonInitialize" AutoGenerateColumns="False">
    <Columns>
        <dx:CardViewTextColumn FieldName="CompanyName" />
        <dx:CardViewTextColumn FieldName="ContactName" />
        <dx:CardViewTextColumn FieldName="City" />
        <dx:CardViewTextColumn FieldName="Region" />
        <dx:CardViewTextColumn FieldName="Country" />
    </Columns>
    <CardLayoutProperties>
        <Items>
            <dx:CardViewCommandLayoutItem HorizontalAlign="Right" ShowSelectCheckbox="True" />
            <dx:CardViewColumnLayoutItem ColumnName="Company Name" />
            <dx:CardViewColumnLayoutItem ColumnName="Contact Name" />
            <dx:CardViewColumnLayoutItem ColumnName="City" />
            <dx:CardViewColumnLayoutItem ColumnName="Region" />
            <dx:CardViewColumnLayoutItem ColumnName="Country" />
            <dx:EditModeCommandLayoutItem HorizontalAlign="Right" />
        </Items>
    </CardLayoutProperties>
</dx:ASPxCardView>  
<asp:AccessDataSource ID="AccessDataSource1" runat="server" DataFile="~/App_Data/nwind.mdb"
    SelectCommand="SELECT * FROM [Customers]" />

protected void ASPxCardView1_CommandButtonInitialize(object sender, DevExpress.Web.ASPxCardViewCommandButtonEventArgs e) {
    if (e.ButtonType == CardViewCommandButtonType.SelectCheckbox)
        e.Visible = !chkDisabled.Checked;
}

Protected Sub ASPxCardView1_CommandButtonInitialize(ByVal sender As Object, ByVal e As DevExpress.Web.ASPxCardViewCommandButtonEventArgs)
    If e.ButtonType = CardViewCommandButtonType.SelectCheckbox Then
        e.Visible = Not chkDisabled.Checked
    End If
End Sub