B
Big Dave
Good morning. I'm new to .net and object oriented programming, and
I'm having a problem that I believe resides on the .net side, but I
can't find a way to correct it within a custom object.
Here's what I'm trying to do. I've built a custom datagrid abstract
object that I will inherit from in custom datagrids built for each
logical business entity within my app. I've marked both the abstract
class and the implementation as <Serializable()>. The datagrid still
does not maintain it's state. I tried manually adding it to viewstate
within my aspx page, and I get the following error:
The type 'System.Web.UI.WebControls.DataGrid' must be marked as
Serializable or have a TypeConverter other than ReferenceConverter to
be put in viewstate.
Description: An unhandled exception occurred during the execution of
the current web request. Please review the stack trace for more
information about the error and where it originated in the code.
Exception Details: System.Web.HttpException: The type
'System.Web.UI.WebControls.DataGrid' must be marked as Serializable or
have a TypeConverter other than ReferenceConverter to be put in
viewstate.
Source Error:
An unhandled exception was generated during the execution of the
current web request. Information regarding the origin and location of
the exception can be identified using the exception stack trace below.
Stack Trace:
[HttpException (0x80004005): The type
'System.Web.UI.WebControls.DataGrid' must be marked as Serializable or
have a TypeConverter other than ReferenceConverter to be put in
viewstate.]
System.Web.UI.LosFormatter.SerializeValue(TextWriter output, Object
value)
System.Web.UI.LosFormatter.SerializeValue(TextWriter output, Object
value)
System.Web.UI.LosFormatter.SerializeValue(TextWriter output, Object
value)
System.Web.UI.LosFormatter.SerializeInternal(TextWriter output,
Object value)
System.Web.UI.LosFormatter.Serialize(TextWriter output, Object
value)
System.Web.UI.LosFormatter.EstimateSize(Object obj)
System.Web.UI.Control.BuildProfileTree(String parentId, Boolean
calcViewState)
System.Web.UI.Page.ProcessRequestMain()
I've looked everywhere I can think of, and I can't get it to work. I
even tried changing the code to just have a function that returns a
standard data grid set with all the columns/properties I want, so it's
no longer a custom server control, just a regular datagrid, and I'm
still getting the same error. Examples of the code with that change
are posted below. Does anybody know what I'm doing wrong? Any help
would be greatly appreciated! Sorry for such a long post.
NEW CODE USING RETURNING STANDARD DATAGRID:
Imports System.Data.OleDb
Imports poker_system.StoredProcedures
Namespace CommandObjects
Public Class SessionDA
Inherits CommandObjects.DataAccessAbstract
Public Sub New()
MyBase.new()
End Sub
#Region " Command Objects "
'code removed to keep this post a little smaller, i don't think this
has anything to do with the issue
#End Region
#Region " Poker Session Methods "
Public Function GetDataAdapter() As OleDbDataAdapter
Dim da As New OleDbDataAdapter
da.SelectCommand = Me.GetSelectAllCommand
Return da
End Function
Public Function GetDataSet() As DataSet
Dim SessionDS As New PokerSessionDS 'my typed dataset
Dim BetTypeDA As New OleDbDataAdapter
BetTypeDA = GetBetTypeDA()
BetTypeDA.Fill(SessionDS.BetType)
Dim SessionDA As New OleDbDataAdapter
SessionDA = GetDataAdapter()
SessionDA.Fill(SessionDS.poker_session)
Return SessionDS
End Function
Public Function GetSessionDataGrid() As DataGrid
Dim dg As New PokerSessionDG
dg.LoadGrid(Me.GetDataSet)
Return dg.GetDataGrid
End Function
#End Region
'code removed to keep this post a little smaller, i don't
think this has anything to do with the issue
#Region " Bet Type Methods "
'code removed to keep this post a little smaller, i don't
think this has anything to do with the issue
#End Region
End Class
End Namespace
CUSTOM OBJECT THAT RETURNS THE DATAGRID
Imports System.ComponentModel
Imports System.Web.UI
<DefaultProperty("Text"), Serializable(),
TypeConverter(GetType(System.ComponentModel.ComponentConverter)),
ToolboxData("<{0}
okerSessionDG runat=server></{0}okerSessionDG>")>
_
Public Class PokerSessionDG
Inherits WebControl
Private dg As DataGrid
Private _sessionDataSet As PokerSessionDS
Public ReadOnly Property SessionDataGrid() As DataGrid
Get
Return dg
End Get
End Property
Public Property SessionDataSet() As PokerSessionDS
Get
Return _sessionDataSet
End Get
Set(ByVal Value As PokerSessionDS)
_sessionDataSet = Value
End Set
End Property
Public Function GetDataGrid() As DataGrid
Return dg
End Function
Public Sub LoadGrid(ByVal ds As DataSet)
Me._sessionDataSet = ds
dg.DataSource = Me._sessionDataSet.poker_session
dg.AutoGenerateColumns = False
dg.EnableViewState = True
dg.Columns.Add(GetEditColumn())
dg.Columns.Add(GetSessionId())
dg.Columns.Add(Me.GetSessionDt())
Me.Controls.Add(dg)
End Sub
Public Sub New()
dg = New DataGrid
End Sub
Private Function GetSessionDt() As BoundColumn
Dim bc As New BoundColumn
bc.DataField =
Me._sessionDataSet.poker_session.session_dtColumn.ToString
bc.HeaderText = "Date Played"
Return bc
End Function
Private Function GetSessionId() As BoundColumn
Dim bc As New BoundColumn
bc.DataField =
Me._sessionDataSet.poker_session.session_idColumn.ToString
bc.HeaderText = "Session Id"
Return bc
End Function
Private Function GetEditColumn() As EditCommandColumn
Dim ec As New EditCommandColumn
ec.CancelText = "Cancel"
ec.EditText = "Edit"
ec.UpdateText = "Update"
Return ec
End Function
Protected Overrides Sub Render(ByVal output As
System.Web.UI.HtmlTextWriter)
Me.RenderChildren(output)
End Sub
Public Sub BindGrid()
dg.DataBind()
End Sub
End Class
ASPX PAGE SUBROUTINE CALLING THE PREVIOUS CODE
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
'Put user code to initialize the page here
Dim PokerSessionDA As New CommandObjects.SessionDA
SessionDataGrid = PokerSessionDA.GetSessionDataGrid
If Me.IsPostBack = False Then
SessionDataGrid.DataBind()
Viewstate.Add("datagrid", SessionDataGrid)
Else
SessionDataGrid = ViewState("Datagrid")
End If
End Sub
OLD CODE, THE WAY I WOULD HAVE LIKED TO DO IT, BUT I CHANGED IT WHEN
THIS DIDN'T WORK
Here is an example of the custom grid I built that also wouldn't
serialize:
Imports System.ComponentModel
Imports System.Web.UI
<DefaultProperty("Text"), Serializable(),
ToolboxData("<{0}okerSessionDG runat=server></{0}okerSessionDG>")>
_
Public Class PokerSessionDG
Inherits CustomControls.CustomDataGrid.CustDataGrid
Private dg As DataGrid
Private _sessionDataSet As PokerSessionDS
Public Property SessionDataSet() As PokerSessionDS
Get
Return _sessionDataSet
End Get
Set(ByVal Value As PokerSessionDS)
_sessionDataSet = Value
End Set
End Property
Public Overrides Sub LoadGrid(ByVal ds As DataSet)
Me._sessionDataSet = ds
MyBase.DataSource = Me._sessionDataSet.poker_session
MyBase.AutoGenerateColumns = False
MyBase.EnableViewState = True
MyBase.Columns.Add(GetEditColumn())
MyBase.Columns.Add(GetSessionId())
MyBase.Columns.Add(Me.GetSessionDt())
MyBase.Controls.Add(dg)
End Sub
Public Sub New()
MyBase.new()
End Sub
Private Function GetSessionDt() As BoundColumn
Dim bc As New BoundColumn
bc.DataField =
Me._sessionDataSet.poker_session.session_dtColumn.ToString
bc.HeaderText = "Date Played"
Return bc
End Function
Private Function GetSessionId() As BoundColumn
Dim bc As New BoundColumn
bc.DataField =
Me._sessionDataSet.poker_session.session_idColumn.ToString
bc.HeaderText = "Session Id"
Return bc
End Function
Private Function GetEditColumn() As EditCommandColumn
Dim ec As New EditCommandColumn
ec.CancelText = "Cancel"
ec.EditText = "Edit"
ec.UpdateText = "Update"
Return ec
End Function
Protected Overrides Sub Render(ByVal output As
System.Web.UI.HtmlTextWriter)
MyBase.Render(output)
End Sub
Public Overrides Sub BindGrid()
MyBase.DataBind()
End Sub
End Class
And here is the abstract class that it inherits
Imports System.ComponentModel
Imports System.Web.UI
Namespace CustomDataGrid
<DefaultProperty("Text"), Serializable(),
ToolboxData("<{0}:CustDataGrid runat=server></{0}:CustDataGrid>")> _
Public MustInherit Class CustDataGrid
Inherits System.Web.UI.WebControls.DataGrid
Private dg As New WebControls.DataGrid
Protected Overrides Sub Render(ByVal output As
System.Web.UI.HtmlTextWriter)
MyBase.Render(output)
End Sub
Public MustOverride Sub BindGrid()
Public MustOverride Sub LoadGrid(ByVal ds As DataSet)
Public Sub New()
MyBase.CellPadding = 3
End Sub
Protected Overrides Sub CreateControlHierarchy(ByVal
useDataSource As Boolean)
MyBase.CreateControlHierarchy(useDataSource)
End Sub
Protected Overrides Sub PrepareControlHierarchy()
MyBase.PrepareControlHierarchy()
End Sub
End Class
End Namespace
I'm having a problem that I believe resides on the .net side, but I
can't find a way to correct it within a custom object.
Here's what I'm trying to do. I've built a custom datagrid abstract
object that I will inherit from in custom datagrids built for each
logical business entity within my app. I've marked both the abstract
class and the implementation as <Serializable()>. The datagrid still
does not maintain it's state. I tried manually adding it to viewstate
within my aspx page, and I get the following error:
The type 'System.Web.UI.WebControls.DataGrid' must be marked as
Serializable or have a TypeConverter other than ReferenceConverter to
be put in viewstate.
Description: An unhandled exception occurred during the execution of
the current web request. Please review the stack trace for more
information about the error and where it originated in the code.
Exception Details: System.Web.HttpException: The type
'System.Web.UI.WebControls.DataGrid' must be marked as Serializable or
have a TypeConverter other than ReferenceConverter to be put in
viewstate.
Source Error:
An unhandled exception was generated during the execution of the
current web request. Information regarding the origin and location of
the exception can be identified using the exception stack trace below.
Stack Trace:
[HttpException (0x80004005): The type
'System.Web.UI.WebControls.DataGrid' must be marked as Serializable or
have a TypeConverter other than ReferenceConverter to be put in
viewstate.]
System.Web.UI.LosFormatter.SerializeValue(TextWriter output, Object
value)
System.Web.UI.LosFormatter.SerializeValue(TextWriter output, Object
value)
System.Web.UI.LosFormatter.SerializeValue(TextWriter output, Object
value)
System.Web.UI.LosFormatter.SerializeInternal(TextWriter output,
Object value)
System.Web.UI.LosFormatter.Serialize(TextWriter output, Object
value)
System.Web.UI.LosFormatter.EstimateSize(Object obj)
System.Web.UI.Control.BuildProfileTree(String parentId, Boolean
calcViewState)
System.Web.UI.Page.ProcessRequestMain()
I've looked everywhere I can think of, and I can't get it to work. I
even tried changing the code to just have a function that returns a
standard data grid set with all the columns/properties I want, so it's
no longer a custom server control, just a regular datagrid, and I'm
still getting the same error. Examples of the code with that change
are posted below. Does anybody know what I'm doing wrong? Any help
would be greatly appreciated! Sorry for such a long post.
NEW CODE USING RETURNING STANDARD DATAGRID:
Imports System.Data.OleDb
Imports poker_system.StoredProcedures
Namespace CommandObjects
Public Class SessionDA
Inherits CommandObjects.DataAccessAbstract
Public Sub New()
MyBase.new()
End Sub
#Region " Command Objects "
'code removed to keep this post a little smaller, i don't think this
has anything to do with the issue
#End Region
#Region " Poker Session Methods "
Public Function GetDataAdapter() As OleDbDataAdapter
Dim da As New OleDbDataAdapter
da.SelectCommand = Me.GetSelectAllCommand
Return da
End Function
Public Function GetDataSet() As DataSet
Dim SessionDS As New PokerSessionDS 'my typed dataset
Dim BetTypeDA As New OleDbDataAdapter
BetTypeDA = GetBetTypeDA()
BetTypeDA.Fill(SessionDS.BetType)
Dim SessionDA As New OleDbDataAdapter
SessionDA = GetDataAdapter()
SessionDA.Fill(SessionDS.poker_session)
Return SessionDS
End Function
Public Function GetSessionDataGrid() As DataGrid
Dim dg As New PokerSessionDG
dg.LoadGrid(Me.GetDataSet)
Return dg.GetDataGrid
End Function
#End Region
'code removed to keep this post a little smaller, i don't
think this has anything to do with the issue
#Region " Bet Type Methods "
'code removed to keep this post a little smaller, i don't
think this has anything to do with the issue
#End Region
End Class
End Namespace
CUSTOM OBJECT THAT RETURNS THE DATAGRID
Imports System.ComponentModel
Imports System.Web.UI
<DefaultProperty("Text"), Serializable(),
TypeConverter(GetType(System.ComponentModel.ComponentConverter)),
ToolboxData("<{0}
okerSessionDG runat=server></{0}okerSessionDG>")>_
Public Class PokerSessionDG
Inherits WebControl
Private dg As DataGrid
Private _sessionDataSet As PokerSessionDS
Public ReadOnly Property SessionDataGrid() As DataGrid
Get
Return dg
End Get
End Property
Public Property SessionDataSet() As PokerSessionDS
Get
Return _sessionDataSet
End Get
Set(ByVal Value As PokerSessionDS)
_sessionDataSet = Value
End Set
End Property
Public Function GetDataGrid() As DataGrid
Return dg
End Function
Public Sub LoadGrid(ByVal ds As DataSet)
Me._sessionDataSet = ds
dg.DataSource = Me._sessionDataSet.poker_session
dg.AutoGenerateColumns = False
dg.EnableViewState = True
dg.Columns.Add(GetEditColumn())
dg.Columns.Add(GetSessionId())
dg.Columns.Add(Me.GetSessionDt())
Me.Controls.Add(dg)
End Sub
Public Sub New()
dg = New DataGrid
End Sub
Private Function GetSessionDt() As BoundColumn
Dim bc As New BoundColumn
bc.DataField =
Me._sessionDataSet.poker_session.session_dtColumn.ToString
bc.HeaderText = "Date Played"
Return bc
End Function
Private Function GetSessionId() As BoundColumn
Dim bc As New BoundColumn
bc.DataField =
Me._sessionDataSet.poker_session.session_idColumn.ToString
bc.HeaderText = "Session Id"
Return bc
End Function
Private Function GetEditColumn() As EditCommandColumn
Dim ec As New EditCommandColumn
ec.CancelText = "Cancel"
ec.EditText = "Edit"
ec.UpdateText = "Update"
Return ec
End Function
Protected Overrides Sub Render(ByVal output As
System.Web.UI.HtmlTextWriter)
Me.RenderChildren(output)
End Sub
Public Sub BindGrid()
dg.DataBind()
End Sub
End Class
ASPX PAGE SUBROUTINE CALLING THE PREVIOUS CODE
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
'Put user code to initialize the page here
Dim PokerSessionDA As New CommandObjects.SessionDA
SessionDataGrid = PokerSessionDA.GetSessionDataGrid
If Me.IsPostBack = False Then
SessionDataGrid.DataBind()
Viewstate.Add("datagrid", SessionDataGrid)
Else
SessionDataGrid = ViewState("Datagrid")
End If
End Sub
OLD CODE, THE WAY I WOULD HAVE LIKED TO DO IT, BUT I CHANGED IT WHEN
THIS DIDN'T WORK
Here is an example of the custom grid I built that also wouldn't
serialize:
Imports System.ComponentModel
Imports System.Web.UI
<DefaultProperty("Text"), Serializable(),
ToolboxData("<{0}
okerSessionDG runat=server></{0}okerSessionDG>")>_
Public Class PokerSessionDG
Inherits CustomControls.CustomDataGrid.CustDataGrid
Private dg As DataGrid
Private _sessionDataSet As PokerSessionDS
Public Property SessionDataSet() As PokerSessionDS
Get
Return _sessionDataSet
End Get
Set(ByVal Value As PokerSessionDS)
_sessionDataSet = Value
End Set
End Property
Public Overrides Sub LoadGrid(ByVal ds As DataSet)
Me._sessionDataSet = ds
MyBase.DataSource = Me._sessionDataSet.poker_session
MyBase.AutoGenerateColumns = False
MyBase.EnableViewState = True
MyBase.Columns.Add(GetEditColumn())
MyBase.Columns.Add(GetSessionId())
MyBase.Columns.Add(Me.GetSessionDt())
MyBase.Controls.Add(dg)
End Sub
Public Sub New()
MyBase.new()
End Sub
Private Function GetSessionDt() As BoundColumn
Dim bc As New BoundColumn
bc.DataField =
Me._sessionDataSet.poker_session.session_dtColumn.ToString
bc.HeaderText = "Date Played"
Return bc
End Function
Private Function GetSessionId() As BoundColumn
Dim bc As New BoundColumn
bc.DataField =
Me._sessionDataSet.poker_session.session_idColumn.ToString
bc.HeaderText = "Session Id"
Return bc
End Function
Private Function GetEditColumn() As EditCommandColumn
Dim ec As New EditCommandColumn
ec.CancelText = "Cancel"
ec.EditText = "Edit"
ec.UpdateText = "Update"
Return ec
End Function
Protected Overrides Sub Render(ByVal output As
System.Web.UI.HtmlTextWriter)
MyBase.Render(output)
End Sub
Public Overrides Sub BindGrid()
MyBase.DataBind()
End Sub
End Class
And here is the abstract class that it inherits
Imports System.ComponentModel
Imports System.Web.UI
Namespace CustomDataGrid
<DefaultProperty("Text"), Serializable(),
ToolboxData("<{0}:CustDataGrid runat=server></{0}:CustDataGrid>")> _
Public MustInherit Class CustDataGrid
Inherits System.Web.UI.WebControls.DataGrid
Private dg As New WebControls.DataGrid
Protected Overrides Sub Render(ByVal output As
System.Web.UI.HtmlTextWriter)
MyBase.Render(output)
End Sub
Public MustOverride Sub BindGrid()
Public MustOverride Sub LoadGrid(ByVal ds As DataSet)
Public Sub New()
MyBase.CellPadding = 3
End Sub
Protected Overrides Sub CreateControlHierarchy(ByVal
useDataSource As Boolean)
MyBase.CreateControlHierarchy(useDataSource)
End Sub
Protected Overrides Sub PrepareControlHierarchy()
MyBase.PrepareControlHierarchy()
End Sub
End Class
End Namespace