This is a classic problem, unfortunately. You'd think it would have been fixed by now, natively I mean ... but no, it hasn't been.

Here's the first paragraph from a blog post I wrote a few months back that sort of explains what's going on (I've also posted this stuff on this forum somewhere, probably more than a few times <g>):

Data in a DataRow has several different versions. First, there's the original version. Then, when it's being edited (either in a UI control, like a TextBox or programmatically), it has a Proposed version and once it's done being edited, that becomes the Current version. Sometimes when entering data in a UI control, the row is left in the Proposed state and the Edit needs to be ended programmatically. This doesn't always happen and I'm not entirely sure why it's seemingly random (maybe it's an ADO.NET bug).

Anyway, the solution that I've always used is posted on my blog entry here: http://geek-goddess-bonnie.blogspot.com/2009/09/fun-with-datasets.html

~~Bonnie







>Hi Viv -
>
>Sorry I didn't reply to this sooner but that answer was, at the time, I don't know. i had run off in so many different directions chasing this that I wasn't sure which parts worked and which didn't.
>
>i think now the answer is that I have solved the serialization, which turned out to be easier than I was making it ( code below for lurkers ) and now have it reduced to a problem with Datagridviews using the dataset member as a datasource. (explained below and my current source of frustration)
>
>That first :
>
>I created a small test app with one table, three columns
>ikey int pk
>company varchar(100)
>wideobject varbinary(max)
>
>I have a dataset (Typedchildset) with two datatables ( Clients, Employees)
>
>I have 2 dgvs. For simplicity, I am binding them to the dataset member rather than using a binding source
>
>I enter data the two grids - Clients, then Employees.
>
>Everything saves when serialized as expected - except the last new row of the last grid.
>
>I can add five rows to employees and all save the last will be saved.
>
>NOTE : on further testing - the problem only comes about if the cursor is still in the newly added row when the save is called. If I first click out of the grid to another control, then save, the last row is saved. But of course, the use won't do that, so i must force something so the endedit actually ends the edit for that row.
>
>In the BeforeSave event of my business object :
>
>

>
>'Tried me.txtCompany.focus() before the code below, as actaully clicking the textbox to get out of the grid before clicking the Save button seems to work - no joy
>
>' I found I needed this before the endedits or I also lost the last new row of the first grid
> 
>      Me.TypedChildset1.AcceptChanges()
>
>        Me.dgvClients.EndEdit()
>        Me.dgvEmployees.EndEdit()
>
>' 
>
>' Here's the serializer - works fine ( note : remotingformat prop of ds instance must be 
>' set to binary
>
>        '-- Copy dataset to property
>
>        '-- Establish locals
>        Dim loFormatter As New BinaryFormatter()
>        Dim loStream As New System.IO.MemoryStream()
>
>        '-- Serialize the business object
>        loFormatter.Serialize(loStream, Me.TypedChildset1)
>
>        '-- Return the created stream
>        Me.CompaniesBO1.WideObject = loStream.ToArray()
>

>
>Feel I'm getting very very close, but this last bit is making me crazi(er).
>
>Thoughts?
>
>
>>Hi,
>>Did you solve this?,
>>Best,
>>Viv
>>
>>>I have a varchar(max) field in SQL 2008 Dataset_XML. My strongly typed business object is mapped to that column, and returns
>>>

>>><dsPolicies xmlns="http://tempuri.org/dsPolicies.xsd" /> 
>>>

>>>for a null. ( this is because I am adding this field to a current app an have to allow nulls, but I could script this as a value for all null values and then not allow nulls if that would help)
>>>
>>>dsPolicies is dropped on the form and the instance is names dsPolicies1.
>>>
>>>The dataset is typed with 8 tables. and the XSD file seems to be working as I am using bindingsources for each table and the datagridviews are showing the right columns.
>>>
>>>In the parentform_loading event of the business object on the Policies form I am trying to deserialize the XML stored in Me.PoliciesBO1.Dataset_XML ( which has the default value shown above) using this code :
>>>
>>>

>>>    Private Sub PoliciesBO1_ParentFormLoading() Handles PoliciesBO1.ParentFormLoading
>>>
>>>        Me.PoliciesBO1.fillall()
>>>
>>>        If Me.PoliciesBO1.Count > 0 Then
>>>
>>>            Me.DsPolicies1 = _ CType(InsurtecPW.Base.Utility.SmartDeSerialize(Me.PoliciesBO1.Dataset_XML), InsurtecPW.dsPolicies)
>>>
>>>        End If
>>>
>>>    End Sub
>>>

>>>
>>>and this is the deserialize routine :
>>>

>>>    Public Shared Function SmartDeSerialize(ByVal serialized As String) As DataSet
>>>        Dim __ds As DataSet = New DataSet
>>>        ' needed to create an XML TextReader 
>>>        Dim nt As NameTable = New NameTable
>>>        Dim nsmgr As XmlNamespaceManager = New XmlNamespaceManager(nt)
>>>        Dim context As XmlParserContext = New XmlParserContext(Nothing, nsmgr, Nothing, XmlSpace.None)
>>>        Dim tr As XmlTextReader = New XmlTextReader(serialized, XmlNodeType.Document, context)
>>>        Try
>>>
>>>            __ds.ReadXml(tr)
>>>
>>>            Return __ds
>>>        Finally
>>>            If Not (tr Is Nothing) Then
>>>                tr.Close()
>>>                tr = Nothing
>>>            End If
>>>            context = Nothing
>>>            nsmgr = Nothing
>>>            nt = Nothing
>>>
>>>        End Try
>>>
>>>    End Function
>>>

>>>
>>>As you see, this returns a dataset, but I don't seem to be able to cast the return value as the dsPolicies that I need.
>>>
>>>Unable to cast object of type 'System.Data.DataSet' to type 'InsurtecPW.dsPolicies'.
>>>
>>>I have also tried a directcast of the returned dataset and got the same result.
>>>
>>>This approach seemed to work find when I was using an untyped dataset.
>>>
>>>I'd appreciate any thoughts on this. I'm pretty clueless about possible differences between the dataset class and a typed dataset or if my problem is the value I am returning if the column is empty.
>>>
>>>I am open to any approach (including serializing to a byte array) which will allow me to write and entire dataset to a sql column and bring it back.
>>>
>>>Suggestions very much appreciated.
>>>
>>>TIA