new error - Column is read only

[Rico]

I have some code that was previously working, taking items from one window
and adding them to another. I changed some code around to only add the
dataset tables if no tables exist rather than running a try catch. I
wouldn't think this would have anything to do with setting anything read
only or not, but now when I try to set the "Selected" value in the datatable
(datarow actually) I get "Column 'selected' is read only". When I do a
debug.writeline(MyDs.Tables("TableName").IsReadOnly) the answer is "False".
Is there something I'm missing? Can anyone provide a reason why the datarow
might be read only?

Here are the three items that make up the code;

------ Part One------
Private Sub LoadData()

Dim daOrders As New OleDb.OleDbDataAdapter

Dim LastColumn As String

Try

'Dim sql$ = "SELECT 0 AS Selected,
VendorInventoryTypes.VendorInventoryTypesID, VendorInventoryTypes.Code,
VendorInventoryTypes.Category, VendorInventoryTypes.SubCategory,
VendorInventoryTypes.Brand, VendorInventoryTypes.Model,
VendorInventoryTypes.Description, 0 AS Quantity,
VendorInventoryTypes.RequiresUniqueItems,VendorInventoryTypes.Cost FROM
(VendorInventoryTypes) WHERE (((VendorInventoryTypes.VendorID)=" &
lclVendorID & "));"

If dsInventoryTypeOrders.Tables.Count = 0 Then

Dim sql$ = getOrderDetailSQL("(((VendorInventoryTypes.VendorID)=" &
lclVendorID & "))")

daOrders = mdi.dt.GenericDA(sql)

dsInventoryTypeOrders.Tables.Add("Orders")

daOrders.FillSchema(dsInventoryTypeOrders.Tables("Orders"),
SchemaType.Source)

Dim dc As New DataColumn

dc.AutoIncrement = True

dc.AutoIncrementSeed = -1

dc.AutoIncrementStep = -1

dc.Unique = True

dc.ColumnName = "GUID"



dsInventoryTypeOrders.Tables("Orders").Columns.Add(dc)

dsInventoryTypeOrders.Tables.Add("OrderDetails")

daOrderDetails = mdi.dt.GenericDA("SELECT * FROM VendorOrderItems")

daOrderDetails.FillSchema(dsInventoryTypeOrders.Tables("OrderDetails"),
SchemaType.Source)

dsInventoryTypeOrders.Tables.Add("SerialDetails")

daOrderDetails.FillSchema(dsInventoryTypeOrders.Tables("SerialDetails"),
SchemaType.Source)

daOrderDetails = mdi.dt.GenericDA("SELECT * FROM VendorOrderItems")

daOrderDetails.FillSchema(dsInventoryTypeOrders.Tables("OrderDetails"),
SchemaType.Source)

End If

daOrders.Fill(dsInventoryTypeOrders, "Orders")

view1 = New DataView(dsInventoryTypeOrders.Tables("Orders"))

view1.RowFilter = "Selected = 0"

view2 = New DataView(dsInventoryTypeOrders.Tables("Orders"))

view2.RowFilter = "Selected = 1"



listAvailable.DataSource = view1

listSelected.DataSource = view2

Catch ex As Exception '

MsgBox(ex.Message, MsgBoxStyle.Critical, "VendorEdit.LoadData")

End Try

End Sub



----- Part Two------



Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles btnAdd.Click, listAvailable.DoubleClick

Try

Dim i As Long

Dim r As DataRow

'If nothing is selected or there is nothing in the list, exit

If listAvailable.Items.Count = 0 Or listAvailable.SelectedIndex < 0 Then

Exit Sub

'If the quantity is not numeric then exit

ElseIf Not IsNumeric(txtQuantity.Text) Then

MsgBox("Quantity must be a numeric value.", MsgBoxStyle.Critical, "Non
Numeric Quantity")

Exit Sub

'Ifthe Quantity has a decimal place in it, then exit

ElseIf Fix(txtQuantity.Text) <> txtQuantity.Text Then

MsgBox("Quantity must be an integer.", MsgBoxStyle.Critical, "No Deciman
Places Allowed")

Exit Sub

'if the quantity has a decimal like format, then remove the decimal place
and trailing zero(s)

ElseIf txtQuantity.Text Like "*.*" Then

txtQuantity.Text = Microsoft.VisualBasic.Left(txtQuantity.Text, InStr(1,
txtQuantity.Text, ".") - 1)

End If

' i = listAvailable.SelectedIndex

i = view1(i)("VendorInventoryTypesID")

view1 = dsInventoryTypeOrders.Tables("Orders").DefaultView

view1.RowFilter = "VendorInventoryTypesID=" & i



For Each r In dsInventoryTypeOrders.Tables("Orders").Rows

MsgBox(dsInventoryTypeOrders.Tables("Orders").Rows.IsReadOnly)

If r("VendorInventoryTypesID") = i Then

UpdateRow(Me, r, txtQuantity.Text, True)

End If

Next

Catch ex As Exception

MsgBox(ex.Message, MsgBoxStyle.Critical, "VendorReceiveOrder.btnAdd_Click")

End Try

End Sub



---- Part Three ----

Friend Sub UpdateRow(ByVal frm As Form, ByVal r As DataRow, ByVal Quantity
As Long, ByVal SelectRow As Boolean)

r.BeginEdit()

' r("Quantity") = Quantity

If SelectRow Then

r("Selected") = 1

Else

r("Selected") = 0

End If

r.AcceptChanges()

UpdateLists()

End Sub



Any help would be great! Thanks!

 

[W.G. Ryan - MVP]

It looks like the Column in question is the only problem, not the table.
Check the column and see if it's read-only. Is it coming back from the DB
as an expression by any chance? This is a frequent culprit.
"Rico" <r c o l l e n s @ h e m m i n g w a y . c o mREMOVE THIS PART IN
CAPS> wrote in message news:W6hSf.150871$B94.45676@pd7tw3no...

 

[Rico]

Now that you mention it, they are set up in the SQL as manual entries (0 as
Quantity, 0 as Selected), but I'm not sure why it worked before and not now.
Strange. I created a work around by setting the two columns to
readonly=false, but is there a better way to do this?

Rick

 

[W.G. Ryan - MVP]

I'm not sure why it worked before, if you set those values, I'd expect it
wouldn't be able to write to them. You can use Expression property of
DataColumns to do the same thing though and avoid the problem altogether.
http://msdn.microsoft.com/library/d...guide/html/cpconCreatingExpressionColumns.asp
"Rico" <r c o l l e n s @ h e m m i n g w a y . c o mREMOVE THIS PART IN
CAPS> wrote in message news:4NiSf.148771$sa3.45682@pd7tw1no...

 

[Rico]

Thanks WG. I think it might have something to do with the introduction of
the dataadapter, although i was sure it was working after I added the DA.

Thanks for the info!

Rick