Hi for some reason my select row code does not work
My grid definition is below
<telerik:radgrid runat="server" id="RadGridAppointmentList" showfooter="false" width="100%" enableajax="true" showstatusbar="true" allowautomaticinserts="false"
onitemcommand="RadGridAppointmentList_ItemCommand" onitemcreated="RadGridAppointmentList_ItemCreated" AllowMultiRowSelection="false"
allowaddingrecords="false" autogeneratecolumns="false" allowsorting="false" allowpagesizeselection="False" onitemdatabound="OnItemDataBoundHandler" allowautomaticupdates="false"
allowpaging="True" skin="Bootstrap" pagesize="25" onneeddatasource="RadGridAppointmentList_NeedDataSource" onprerender="RadGridAppointmentList_PreRender" cssclass="table table-striped">
<MasterTableView AutoGenerateColumns="false" DataKeyNames="ref" TableLayout="Auto" EditMode="EditForms" CommandItemDisplay="None" >
<Columns>
<telerik:GridTemplateColumn UniqueName="CheckBoxTemplateColumn" AllowFiltering="false" HeaderText="Select" ItemStyle-Width="45" HeaderStyle-Width="45" HeaderStyle-BackColor="#428bca" HeaderStyle-ForeColor="White" HeaderStyle-Font-Bold="true">
<ItemTemplate>
<asp:CheckBox ID="CheckBox1" OnCheckedChanged="CheckUncheckItem" AutoPostBack="True"
runat="server"></asp:CheckBox>
</ItemTemplate>
</telerik:GridTemplateColumn>
<telerik:GridButtonColumn CommandName="Edit" UniqueName="EditColumn" Text="Edit" ItemStyle-Width="45px" HeaderText="Edit" HeaderStyle-BackColor="#428bca" HeaderStyle-ForeColor="White" HeaderStyle-Font-Bold="true">
</telerik:GridButtonColumn>
<telerik:GridBoundColumn DataField="ref" runat="server" Display="false" ItemStyle-Width="1" ItemStyle-ForeColor="White" UniqueName="ref">
</telerik:GridBoundColumn>
<telerik:GridBoundColumn UniqueName="studentname" DataField="" HeaderText="Name" runat="server" ItemStyle-Wrap="true" HeaderStyle-BackColor="#428bca" HeaderStyle-ForeColor="White" HeaderStyle-Font-Bold="true"
ItemStyle-Width="100" ReadOnly="true">
</telerik:GridBoundColumn>
<telerik:GridBoundColumn UniqueName="Id_No" DataField="id_no" HeaderText="Student" runat="server" ItemStyle-Width="30px"
Display="false" ReadOnly="true">
</telerik:GridBoundColumn>
<telerik:GridBoundColumn UniqueName="bookeddate" DataField="bookeddate" HeaderText="Date" HeaderStyle-HorizontalAlign="Center" ItemStyle-HorizontalAlign="Left" runat="server"
ItemStyle-Width="100" Display="false">
</telerik:GridBoundColumn>
<telerik:GridBoundColumn DataField="selectedtime" HeaderText="Time" runat="server" ItemStyle-Width="80" Display ="false">
</telerik:GridBoundColumn>
<telerik:GridBoundColumn UniqueName="appointmentdate" HeaderText="Date and Time" runat="server" ItemStyle-Width="110px" HeaderStyle-BackColor="#428bca" HeaderStyle-ForeColor="White" HeaderStyle-Font-Bold="true">
</telerik:GridBoundColumn>
<telerik:GridBoundColumn DataField="staff_id" HeaderText="Name" runat="server" ItemStyle-Width="100px" Display="false">
</telerik:GridBoundColumn>
<telerik:GridBoundColumn UniqueName="staff_name" DataField="" HeaderText="Staff Name" runat="server" HeaderStyle-BackColor="#428bca" HeaderStyle-ForeColor="White" HeaderStyle-Font-Bold="true" ItemStyle-Width="100" Display="true">
</telerik:GridBoundColumn>
<telerik:GridBoundColumn DataField="status" HeaderText="Status" HeaderStyle-BackColor="#428bca" HeaderStyle-ForeColor="White" HeaderStyle-Font-Bold="true" UniqueName="status"
runat="server" ItemStyle-Width="130px">
</telerik:GridBoundColumn>
</Columns>
<EditFormSettings EditFormType="Template">
<EditColumn UniqueName="EditColumn">
</EditColumn>
<FormTemplate>
<table style="width: 100%" border="0" >
<tr style="border:solid">
<td colspan="2"><b>Edit Appointment</b><br /></td>
</tr>
<tr>
<td colspan="2">
<br />
Select Status<br />
<telerik:RadComboBox ID="RadComboBoxStatus" runat="server" EmptyMessage="Select Status" CausesValidation="False"
HighlightTemplatedItems="true" Height="100px" Width="450px" DropDownWidth="450px" EnableAutomaticLoadOnDemand="False" AutoPostBack="true"
AppendDataBoundItems="true" Visible="true" CssClass="ComboBox" OnSelectedIndexChanged="RadComboBoxStatus_SelectedIndexChanged">
<Items>
<telerik:RadComboBoxItem value="absent" text="absent" />
<telerik:RadComboBoxItem value="present" text="present" />
<telerik:RadComboBoxItem value="session_cancelled" text="session_cancelled" />
</Items>
</telerik:RadComboBox>
</td>
</tr>
<tr>
<td colspan="2">
<asp:Button ID="btnSave" CausesValidation="False" Text="Save"
runat="server" AutoPostBack="True" CommandName="Update"></asp:Button>
</td>
</tr>
</FormTemplate>
</EditFormSettings>
</MasterTableView>
<ClientSettings EnablePostBackOnRowClick="True">
<Selecting AllowRowSelect="true"></Selecting>
</ClientSettings>
<SelectedItemStyle BackColor="Gray" BorderColor="Blue" BorderStyle="Dashed" BorderWidth="1px" />
</telerik:radgrid>
This is my select code
Protected Sub CheckUncheckItem(sender As Object, e As EventArgs)
Dim selectedItems As ArrayList
TryCast(TryCast(sender, CheckBox).NamingContainer, GridItem).Selected = TryCast(sender, CheckBox).Checked
Dim CheckBox1 As CheckBox = DirectCast(sender, CheckBox)
Dim item As GridDataItem = DirectCast(CheckBox1.NamingContainer, GridDataItem)
If CheckBox1.Checked Then
Dim refno As String = item.GetDataKeyValue("ref").ToString()
selectedItems.Add(refno)
Session("selectedItems") = selectedItems
Else
Dim refno As String = item.GetDataKeyValue("ref").ToString()
selectedItems.Remove(refno)
Session("selectedItems") = selectedItems
End If
End Sub
The line selectedItems.Add(refno) is failing
Error is Error Message: Object reference not set to an instance of an object.
Does the ref column need to be visible to make it work?