Web Development

Implements INamingContainer

'System.Web.UI.IPostBackDataHandler.LoadPostData' is already implemented by base class 'System.Web.UI.WebControls.ListBox' and cannot be implemented again.

Protected Overrides Sub OnLoad(ByVal e As System.EventArgs)
    MyBase.OnInit(e)
    Try
        If Page.IsPostBack() Then
            ' The page can have many instances of this component, so don't want to push the
            ' cwcComboBoxInfo state class instance infomation through the ViewState, so put
            ' a reference to in a session variable, actually done at the end of the Render
            ' Sub.
            '
            ' When the page is posted back, the component state is restored by setting the
             cwcComboBoxInfo to the reference value saved in the  session variable.
            '
            If Not HttpContext.Current.Session(cwcComboBoxInfo.ID) Is Nothing Then
                cwcComboBoxInfo =
                   CType(HttpContext.Current.Session(cwcComboBoxInfo.ID),
                         cwcComboBoxInfoClass)
            End If

            ' Get the postback data.
            LoadPostData()  ' There is a bug in VS.NET 2003 that prevents the LoadPostData
                            ' function from overriding/shadowing the listbox base class's
                            ' IPostBackDataHandler.LoadPostData and RaisePostDataChangeEvent
                            ' implementation, so call the LoadPostData function directly to
                            ' get the posted data.
        End If
    Catch Ex As Exception
        Throw New cwcComboBoxException("OnLoad: Exception - Component " & Me.ID & ", " & _
                                       Ex.Message)
    End Try
End Sub

' -------------------------------------------------------------

' The following was a suggested fix to the IPostBackDataHandler implmentation problem, but
' it didn't seem to help.  Instead, Sebastián Streiger suggested that the Impments ...
' statement should be removed from the LoadPostData function and RaisePostDataChangeEvent Sub
' declarations.  However, while this allowed me to compile the code it doesn't seem to get
' called by the .NET Framework.  So I implmemented a override LoadPostData function with no
' parameters that I directly call from the OnLoad event sub above.

Public Shadows Interface IPostBackDataHandler
    Function LoadPostData(ByVal sPostData As String, _
                          ByVal oPostCollection As NameValueCollection) As Boolean
    Sub RaisePostDataChangedEvent()
End Interface

' -------------------------------------------------------------

Private Enum EventsType
    NoEvent
    TextBoxValueChanged
    SelectedListIndexChanged
End Enum

'
' This "global variable keeps track of the component's event that needs to be raised.
' Part of the IPostBackDataHandler workaround I'm using.
'
Private EventType As EventsType = EventsType.NoEvent

'
' Define a LoadPostData function that can be called from the OnLoad event
' just in case the IPostBackData Handler isn't called by the .NET Framework.
'
Private Function LoadPostData() As Boolean
    Return LoadPostData(cwcComboBoxInfo.ID, Me.Page.Request.Params)
End Function

'
' Should be called by the .NET Framework do allow handling of the PostBack Data for this
' component.  If that doesn't happen then the overload above can be called.
'
Public Overridable Function LoadPostData(ByVal Key As String, _
                                         ByVal PostedValues As NameValueCollection) _
                                         As Boolean
    '
    ' Implements System.Web.UI.IPostBackDataHandler.LoadPostData
    '
    Dim Values As String() = PostedValues.GetValues(cwcComboBoxInfo.ID)
    Dim OldValue, NewValue As String
    Dim Result As Boolean


    Select Case Values.Length
        Case 0
            ' Use the component's custom exception
            EventType = EventsType.NoEvent
            Throw New cwcComboBoxException("LoadPostData: Exception - " & _
                                           "No data found for the '" & _
                                           cwcComboBoxInfo.ID & "' component!")
        Case 1
            OldValue = [Text]
            NewValue = Values(0).Trim()
            If [IgnoreCase] Then
                Result = (OldValue.ToLower() = NewValue.ToLower())
            Else
                Result = (OldValue = NewValue)
            End If
            If Result Then
                [SelectedListIndex] = NOTHINGSELECTED
                [Text] = NewValue
                EventType = EventsType.TextBoxValueChanged
            End If
        Case 2
            [SelectedListIndex] = Val(Values(1))
            EventType = EventsType.SelectedListIndexChanged
        Case Else
            EventType = EventsType.NoEvent
            Throw New cwcComboBoxException("LoadPostData: Exception - Too much data " & _
                                           "posted for the '" & _
                                           cwcComboBoxInfo.ID & "' component, " & _
                                           Values.Length & " data items " & _
                                           "(" & Me.Page.Request.Params.Get( _
                                                     cwcComboBoxInfo.ID) & ")!")
    End Select
    Return (EventType <> EventsType.NoEvent)
End Function

' -------------------------------------------------------------

Public Event TextBoxValueChanged As EventHandler

Protected Overridable Sub OnTextBoxValueChanged(ByVal Ex As EventArgs)
    RaiseEvent TextBoxValueChanged(Me, Ex)
End Sub

' -------------------------------------------------------------

Public Event SelectListIndexChanged As EventHandler

Protected Overridable Sub OnSelectedListIndexChanged(ByVal Ex As EventArgs)
    RaiseEvent SelectListIndexChanged(Me, Ex)
End Sub

' -------------------------------------------------------------

Public Overridable Shadows Sub RaisePostDataChangedEvent()
    '
    ' Implements IPostBackDataHandler.RaisePostDataChangedEvent
    '
    ' Figures out which event handler to use.
    '
    Select Case EventType
        Case EventsType.NoEvent
            ' No Action - No event occurred.
        Case EventsType.TextBoxValueChanged
            OnTextBoxValueChanged(EventArgs.Empty)
        Case EventsType.SelectedListIndexChanged
            OnSelectedListIndexChanged(EventArgs.Empty)
    End Select
End Sub

howardjr wrote:

So if I understand you, the span nested in side of the table cell is being treated as an inline element, so ignores the text-alignment of the cell, but because it is an inline element also ignores any text-align-ment that I try to force on it with the CSS Style settings.

howardjr wrote:

Therefore, since the span'ed cells show on the right side of the cell, it must be the entire span that's being pushed over there by the table tr td CSS style selector.

Bradml wrote:

As you may have noticed, IE seems to have a thing for not doing what they say.

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<body leftmargin="0" topmargin="0" rightmargin="0" bottommargin="0" marginwidth="0" marginheight="0">
	<table width="100%" height="100%" cellspacing="0" cellpadding="0" border="1">
		<tr>
			<td>1</td>
			<td>2</td>
		</tr>
		<tr>
			<td>3</td>
			<td>4</td>
		</tr>
		<tr>
			<td colspan="2" valign="bottom">5</td>
		</tr>
	</table>
</body>
</html>

Jeremy Falcon wrote:

Also, the main reason I say it's XHTML that's driving me crazy is that it enforces the rule about not caring for the height attrib to a table whereas in HTML you could take advantage of that if CSS wasn't playing fair.

Guffa wrote:

The table tag doesn't have a height attribute at all, it never has and it never will. It's only Internet Explorer that thinks that it has.

Guffa wrote:

The reason that Internet Explorer ignores the heigth attribute when you are using XHTML, is that then it tries to follow the standards and treats it correctly.