SavedOldValues collection and GridTemplateColumn

[Sergey]

Hi
Here's 2 different typed columns. Both have DataField specified

<telerik:GridBoundColumn DataField="ID" UniqueName="ID" Visible="False" >
</telerik:GridBoundColumn>

<telerik:GridTemplateColumn DataField="Name" HeaderText="Name" UniqueName="NameColumn">
<ItemTemplate><%# DataBinder.Eval(Container.DataItem, "Name") %></ItemTemplate>
<EditItemTemplate>
<asp:TextBox ID="tbName" runat="server" SkinID="GeneralTextBox" Text='<%# DataBinder.Eval(Container.DataItem, "Name") %>'></asp:TextBox>
</EditItemTemplate>
</telerik:GridTemplateColumn>

However only "ID" exists in SavedOldValues collection (ItemCommand event):

Telerik.Web.UI.GridDataItem dataItem = e.Item as Telerik.Web.UI.GridDataItem;
dataItem.SavedOldValues["ID"] //this always have a value
dataItem.SavedOldValues["Name"] // this is not exists

Why 'Name' is not contains in SavedOldValues collection when I use GridTemplateColumn?
I'm forced to do selection from dataset by ID to get original 'Name' value

[Princy]

Hi Sergy,

You can retrieve the old values for the edited item through the SavedOldValues property of the GridEditableItem (which is IDictionary collection of key -> value pairs). The keys in this collection are the UniqueNames of the editable columns and the values are the cell content for the edited row before the edit operation. Try setting the proper UniqueName for the GridTemplateColumn.

dataItem.SavedOldValues["NameColumn"]

Thanks
Princy.

[Sebastian]

Hello guys,

Actually for template columns you need to store and retrieve the old values manually with coding. Review this topic from the online documentation which illustrates sample approach:

http://www.telerik.com/help/aspnet-ajax/grdretrieveoriginalvaluesforediteditem.html

Best regards,
Stephen
the Telerik team

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[Lenny_shp]

What is the recommended approach for template column since we can not store a copy into SavedOldValues in ItemDataBound?
I am using InPlace Edit mode.     Do we create a hidden textbox to store it?

[Sebastian]

Hi Lenny_shp,

Indeed if you are restricted from using the ItemDataBound event to store the old value from the textbox editor(s), consider including a hidden textbox inside the edit template of the template column and extract the value from it on update action.

Best,
Sebastian
the Telerik team

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[Scott]

As Sebastian alluded to putting a hidden non-GridTemplateColumn with the template column will also automatically yield a value with the field name you're looking for in the SavedOldValues collection.  This way of course adds to the size of the page but avoids using a session variable.

<%--using hidden field in order to get field value to show up in saved old values collection--%><br><telerik:GridDateTimeColumn DataField="EffectiveDate" Visible="false"></telerik:GridDateTimeColumn><br><telerik:GridTemplateColumn DataField="EffectiveDate" HeaderText="Start Date" ItemStyle-VerticalAlign="Top" DataType="System.String"<br>UniqueName="EffectiveDate" SortExpression="EffectiveDate"><br>. . . <br></telerik:GridTemplateColumn>