Intersoft Community - WebGrid Enterprise - object reference not set to an instance of an object

object reference not set to an instance of an object

andi@intersoftpt.com — Fri, 22 Jan 2010 02:07:40 GMT

Hi Conrad,

The code that you have provided is almost correct, however, you are missing a little thing. Here is the snippet to reference the n-index column in the grid. In here, I am going to display it on TextBox that is why I have to convert the value into a string by .ToString().

              TextBox1.Text = e.Row.Cells[1].Value.ToString();

I hope it helps and please, do not heistate to ask if you have any other questions. Thank you.

Best Regards,

Andi Santoso

object reference not set to an instance of an object

hohenbergerc — Thu, 21 Jan 2010 14:28:25 GMT

Hi Andi,

In reference to the code above, in the WebGrid1_UpdateRow code, I'm trying to reference the second column in the grid. I can reference the first with the code:

e.Rows.Cells(0).value

however when I try to reference the second column with:

e.Rows.Cells(1).Value

I get the dreaded object reference error message.

What am I doing wrong?

Thanks,

Conrad

object reference not set to an instance of an object

andi@intersoftpt.com — Thu, 14 Jan 2010 20:47:06 GMT

Hi Conrad,

Sorry, but I must be forgot to attach the file, apologize for that. In my sample, everything works just fine and I added the DataKeyField to the RootTable element as well. However, it cause no problem at all.

I believe that our WebGrid supports Oracle database as well, so it will not make any different. Thank you.

Best Regards,

Andi Santoso

object reference not set to an instance of an object

hohenbergerc — Thu, 14 Jan 2010 08:02:07 GMT

Andi,

I added the DataKeyField to the RootTable element and it caused problems with the Insert and I still get the same message on Update. Oracle is the database I'm updating. Will that make a difference?

Also, I couldn't find the attachment.

Thanks,

Conrad

object reference not set to an instance of an object

andi@intersoftpt.com — Wed, 13 Jan 2010 22:49:18 GMT

Hi Conrad,

Sorry, but I am not able to repro your issue. I have tried to create a WebGrid using your setting and Northwind SQL database, and the update row works just fine. Here, I attached you my sample file. There might be a workaround for this, but I am not quite sure if it is working or not since I can not repro your issue. Try to add the RootTable DataKeyFiled within your WebGrid. Here the snippet:

<RootTable DataKeyField="HARDWARE_SCHED_CODE" ColumnHeaders="Yes" AllowEdit="Yes" AllowDelete="Yes">

I hope it helps and let me know if it solves your issue. Thank you.

Best Regards,

Andi Santoso

object reference not set to an instance of an object

hohenbergerc — Wed, 13 Jan 2010 16:21:01 GMT

I have a webgrid bound to a sqldatasource. The sqldatasource has SelectCommand, InsertCommand, DeleteCommand and UpdateCommand defined. Whenever I update a row, I get the object reference error. Select, Insert and Delete all work fine. My code is listed below:

<ISWebGrid:WebGrid ID="WebGrid1" runat="server" UseDefaultStyle="True" Width="100%" Height="250px" DataSourceID="SqlDataSource1" OnInitializeRow="WebGrid1_InitializeRow" OnDeleteRow="WebGrid1_DeleteRow" > <LayoutSettings AllowAddNew="Yes" AllowEdit="Yes" NewRowLostFocusAction="AlwaysUpdate" FilterBarVisible="False" allowdelete="Yes" > </LayoutSettings> <RootTable ColumnHeaders="Yes" AllowEdit="Yes" AllowDelete="Yes"> <Columns> <ISWebGrid:WebGridColumn Bound="true" DataMember="HARDWARE_SCHED_CODE" Caption="Hardware Schedule Code" Width="10%" Name="hardware_sched_code" DataType="System.Int32" EditType="NoEdit" /> <ISWebGrid:WebGridColumn Bound="true" DataMember="HARDWARE_SCHED_DESCR" Caption="Description" Width="90%" Name="hardware_sched_descr" DataType="System.String" /> </Columns> </RootTable> </ISWebGrid:WebGrid> <asp:Label runat="server" ID="mess" /> <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:DHOUSE %>" ProviderName="Oracle.DataAccess.Client" SelectCommand="SELECT HARDWARE_SCHED_CODE, HARDWARE_SCHED_DESCR FROM HARDWARE_SCHEDULE WHERE (M2O_ID = :M2O_ID)" InsertCommand="INSERT INTO HARDWARE_SCHEDULE(HARDWARE_SCHED_CODE, HARDWARE_SCHED_DESCR,M2O_ID) VALUES (:hardware_sched_code,:hardware_sched_descr,:M2O_ID)" UpdateCommand="update hardware_schedule set hardware_sched_descr=:hardware_sched_descr WHERE M2O_ID = :M2O_ID and HARDWARE_SCHED_CODE=:hardware_sched_code" DeleteCommand="delete_hardware_schedule" DeleteCommandType="StoredProcedure" > <SelectParameters> <asp:SessionParameter Name="M2O_ID" SessionField="m2o_Id" DbType="Int32" /> </SelectParameters> <InsertParameters> <asp:Parameter Name="hardware_sched_code" DbType="Int32" /> <asp:Parameter Name="hardware_sched_descr" DbType="String" /> <asp:SessionParameter Name="M2O_ID" SessionField="m2o_Id" DbType="Int32" /> </InsertParameters> <UpdateParameters> <asp:querystringParameter Name="hardware_sched_code" DbType="Int32" /> <asp:querystringParameter Name="hardware_sched_descr" DbType="String" /> <asp:SessionParameter Name="M2O_ID" SessionField="m2o_Id" DbType="Int32" /> </UpdateParameters> <DeleteParameters> <asp:Parameter Name="hardware_sched_code" DbType="Int32" /> <asp:SessionParameter Name="M2O_ID" SessionField="m2o_Id" DbType="Int32" /> </DeleteParameters> </asp:SqlDataSource>

Any help wpuld be greatly appreciated. I've read many posts on the Developer Network, but none actually listed an answer.

Thanks,

Conrad