Problem creating DataGrid Template Column programm

fantozunea · Apr 28, 2012

Hi, I am building a DataGrid, which includes a Template Column "ItemText". When the DataGrid goes into Edit Mode, the datafield in this column is displayed in a textbox "tbItemText". The text in this field is quite long (a few thousand words), and contains html tags. I want the user to be able to make changes in the textbox, and then see what his changes will look like when displayed in a browser, BEFORE the database itself is updated. This is how I'm trying to do it: 1 under the textbox tbItemText in Edit Mode there is a button "Proposed Item Text". 2 when the user clicks on this button, a Command Event is raised 3 in the subroutine dg_Command, the existing columns of the DataGrid are made invisible, and a new Template Column (Header: "Proposed Item Text") is dynamically created. 4 This new dynamic Template Column contains an asp:Label Control, id="lbProposedItemText". This label is loaded from a separate file "TEMPLATE.ASCX" via thePage.LoadTemplate("Template.ascx") method. 5 lbProposedItemText.Text is set to equal tbItemText.Text, thus showing the user the results of his proposed changes to ItemText. I am having a problem with step 5 - when the dynamically created Template Column is shown, the Label lbProposedItemText has NO Text attached to it. Can anyone tell me why? Thanks! JON ************************************************** ********************** THE CODE ************************************************** ********************** THE WHOLE LISTING IS QUITE LONG - HERE'S JUST THE SUBROUTINE TO HANDLE THE COMMAND EVENT RAISED WHEN THE "PROPOSED ITEM TEXT" BUTTON IS CLICKED: sub dg_command(sender as object, e as DataGridCommandEventArgs) If e.CommandSource.Text = "View Proposed Changes" Dim tc as new TemplateColumn() tc.HeaderText="Proposed Item Text" tc.ItemTemplate = Page.LoadTemplate("Template.ascx") dg.Columns(0).visible = False dg.Columns(1).visible = False dg.Columns(2).visible = False dg.Columns(3).visible = False dg.Columns(4).visible = False dg.Columns.Add(tc) If (e.Item.ItemType = ListItemType.Item) or (e.Item.ItemType = ListItemType.AlternatingItem) then Dim lbProposedItemText As Label = e.Item.FindControl("lbProposedItemText") Dim tbItemText As TextBox = e.Item.FindControl("tbItemText") lbProposedItemText.Text = tbItemText.Text 'THIS IS NOT WORKING FOR SOME REASON end if dg.DataBind() end if end sub HERE ARE THE FULL LISTINGS OF THE ASCX PAGE AND THE MAIN DATAGRID PAGE: +++++++++++++++++++++++++++++ TEMPLATE.ASCX +++++++++++++++++++++++++++++ <%@ Control Language="VB" %> <asp:Label id="lbProposedItemText" runat="server" /> +++++++++++++++++++++++++++++ MAIN PAGE +++++++++++++++++++++++++++++ <%@ Page Language="VB" Debug="true" %> <%@ Import Namespace="System.Data" %> <%@ Import Namespace="System.Data.Oledb" %> <%@ Reference Control="Template.ascx" %> <script language="VB" runat="server"> Dim objConn as New OleDbConnection ( ConfigurationSettings.AppSettings("ConnectionString") ) Dim ds as Dataset = New DataSet() Dim objAdapter as New OleDbDataAdapter ( "SELECT * from tblItems;", objConn ) Sub Page_Load(sender as object, e as eventargs) objConn.Open() objAdapter.Fill(ds, "tblItems") dg.DataSource = ds dg.DataMember = "tblItems" If Not Page.IsPostBack Then dg.Databind() End If End Sub function EscapeString(str) 'Used to prevent HTML from being entered and to escape any quotation 'marks, necessary so the values can be specified in an input field str = replace(str, "'", "''") escapeString = str end function Sub myDataGrid_ItemDataBound(sender As Object, e As DataGridItemEventArgs) If (e.Item.ItemType = ListItemType.Item) or (e.Item.ItemType = ListItemType.AlternatingItem) then Dim hlViewItemText as new Hyperlink Dim lbItemId As Label = e.Item.FindControl("lbItemID") hlViewItemText.NavigateURL="ViewItemText.aspx?ItemID=" & lbItemID.Text hlViewItemText.Text="ViewItemText" e.Item.FindControl("HyperLinkPlaceHolder").Controls.Add(hlViewItemText) End if 'WHEN IN EDIT MODE, Set the SelectedIndex of the ItemType DropDownList to current ItemType If e.Item.ItemType = ListItemType.EditItem then Dim ddItemType as DropDownList = e.Item.FindControl("ddItemType") Dim lbItemType as Label = e.Item.FindControl("lbItemType") 'lbItemType is a non-visible Label, only in the EditItemTemplate so I can grab the value here! ddItemType.Items.FindByText(lbItemType.Text).Selec ted = true End if End sub sub dg_edit(sender as object, e as DataGridCommandEventArgs) dg.edititemindex = e.item.itemindex dg.databind() end sub sub dg_cancel(sender as object, e as DataGridCommandEventArgs) dg.edititemindex = -1 dg.databind() end sub sub dg_update(sender as object, e as DataGridCommandEventArgs) Dim tbItemTitle As TextBox = e.Item.FindControl("tbItemTitle") Dim tbItemDescription As TextBox = e.Item.FindControl("tbItemDescription") Dim tbItemText As TextBox = e.Item.FindControl("tbItemText") Dim lbItemId As Label = e.Item.FindControl("lbItemID") Dim strSQL As String = "UPDATE tblItems SET ItemTitle = '" & tbItemTitle.Text & "', ItemDescription = '" & tbItemDescription.Text & "' , ItemText = '" & EscapeString(tbItemText.Text) & "' WHERE ItemID = " & lbItemID.Text 'This throws an error if ItemText is empty - but not ALL items WILL have a text! Dim objCommand as New OleDbCommand(strSQL, objConn) objCommand.ExecuteNonQuery() ds.Tables.Clear objAdapter.Fill(ds, "tblItems") dg.edititemindex = -1 dg.DataBind() end sub sub dg_command(sender as object, e as DataGridCommandEventArgs) '************************************************* **************************** 'PROBLEM HERE - WANT TO DYNAMICALLY ADD A TEMPLATE COLUMN WITH A LABEL "PROPOSEDITEMTEXT" 'THEN SET THE TEXT PROPERTY OF THIS LABEL TO EQUAL THE TEXT PROPERTY 'OF THE TEXTBOX ITEMTEXT (FROM ANOTHER COLUMN) '************************************************* **************************** If e.CommandSource.Text = "View Proposed Changes" Dim tc as new TemplateColumn() tc.HeaderText="Proposed ItemText" tc.ItemTemplate = Page.LoadTemplate("Template.ascx") dg.Columns(0).visible = False dg.Columns(1).visible = False dg.Columns(2).visible = False dg.Columns(3).visible = False dg.Columns(4).visible = False dg.Columns.Add(tc) If (e.Item.ItemType = ListItemType.Item) or (e.Item.ItemType = ListItemType.AlternatingItem) then Dim lbProposedItemText As Label = e.Item.FindControl("lbProposedItemText") Dim tbItemText As TextBox = e.Item.FindControl("tbItemText") lbProposedItemText.Text = tbItemText.Text 'THIS IS NOT WORKING FOR SOME REASON end if dg.DataBind() end if end sub </script> <html> <head> <link rel="STYLESHEET" type="text/css" href=http://aspmessageboard.com/archive/index.php/"Forum.css"> </head> <body> <form runat="server"> <asp

ataGrid id="dg" runat="server" Bordercolor="black" gridlines="vertical" font-names="Arial" font-size="10pt" cellpadding="4" cellspacing="0" width="100%" ShowFooter="True" HeaderStyle-BackColor="#cccc99" FooterStyle-BackColor="#cccc99" ItemStyle-BackColor="#ffffff" AlternatingItemStyle-Backcolor="#cccccc" AutoGenerateColumns="False" OnItemDataBound="myDataGrid_ItemDataBound" OnEditCommand="dg_edit" OnCancelCommand="dg_cancel" OnUpdateCommand="dg_update" OnItemCommand="dg_command" > <Columns> <asp:editcommandcolumn HeaderText="EDIT" edittext="Edit" CancelText="Cancel" UpdateText="Save" HeaderText="" /> <%-- ITEMID; ITEMTYPEID; ITEMTYPE; ITEMTITLE --%> <asp:TemplateColumn ItemStyle-VerticalAlign="top" HeaderText="Various"> <ItemTemplate> <asp:Table CSSClass="TableStyle1" runat="server"> <asp:TableRow> <asp:TableCell>ItemID: </asp:TableCell><asp:TableCell><asp:Label id="lbItemID" Text ='<%# DataBinder.Eval(Container.DataItem, "ItemID") %>' runat="server" /></asp:TableCell> <%-- this was originally a bound column, and I was tracking down the ItemID value with e.Item.Cells(1).Text - problem was, if I changed the columns around, I had to manually change the column number, so am now doing it dynamically --%> </asp:TableRow> <asp:TableRow> <asp:TableCell>ItemTypeID: </asp:TableCell><asp:TableCell><asp:Label runat="server" Text='<%# Container.DataItem("ItemTypeID") %>' /></asp:TableCell> </asp:TableRow> <asp:TableRow> <asp:TableCell>ItemType: </asp:TableCell><asp:TableCell><asp:Label runat="server" Text='<%# Container.DataItem("ItemType") %>' /></asp:TableCell> </asp:TableRow> <asp:TableRow> <asp:TableCell>ItemTitle: </asp:TableCell><asp:TableCell><asp:Label runat="server" Text='<%# Container.DataItem("ItemTitle") %>' /></asp:TableCell> </asp:TableRow> </asp:Table> </ItemTemplate> <EditItemTemplate> <asp:Table CSSClass="TableStyle1" runat="server"> <asp:TableRow> <asp:TableCell>ItemID: </asp:TableCell><asp:TableCell><asp:Label id="lbItemID" Text ='<%# DataBinder.Eval(Container.DataItem, "ItemID") %>' runat="server" /></asp:TableCell> </asp:TableRow> <asp:TableRow> <asp:TableCell>ItemTypeID: </asp:TableCell><asp:TableCell><asp:Textbox id="tbItemTypeID" runat="server" Text='<%# Container.DataItem("ItemTypeID") %>' /></asp:TableCell> </asp:TableRow> <asp:TableRow> <asp:TableCell>ItemType: </asp:TableCell><asp:TableCell><asp:Label runat="server" id="lbItemType" Visible="false" Text='<%# Container.DataItem("ItemType") %>' /><asp

ropDownList id="ddItemType" runat="server" DataSource='<%# ds.Tables("tblItems").DefaultView %>' DataTextField="ItemType" /></asp:TableCell> <%-- This row contains a non-visible Label, simply there so I can grab the "current" ItemType from it and set the Selected Item of the Drop Down to this value --%> </asp:TableRow> <asp:TableRow> <asp:TableCell>ItemTitle: </asp:TableCell><asp:TableCell><asp:Textbox id="tbItemTitle" runat="server" Text='<%# Container.DataItem("ItemTitle") %>' /></asp:TableCell> </asp:TableRow> </asp:Table> </EditItemTemplate> </asp:TemplateColumn> <%-- ITEM DESCRIPTION --%> <asp:TemplateColumn HeaderText="ItemDescription"> <ItemTemplate> <asp:Label runat="server" Text='<%# Container.DataItem("ItemDescription")%>' /> </ItemTemplate> <EditItemTemplate> <asp:Textbox id="tbItemDescription" runat="server" Textmode="MultiLine" Columns="30" Rows="8" Text='<%# Container.DataItem("ItemDescription") %>' /> </EditItemTemplate> </asp:TemplateColumn> <%-- ITEM TEXT --%> <asp:TemplateColumn HeaderText="ItemText"> <ItemTemplate> <asp:TextBox runat="server" ReadOnly="True" Textmode="MultiLine" Columns="30" Rows="8" Text='<%# Container.DataItem("ItemText") %>' /> <asp

laceholder runat="server" id="HyperLinkPlaceholder" /> </ItemTemplate> <EditItemTemplate> <asp:TextBox id="tbItemText" runat="server" Textmode="MultiLine" Columns="30" Rows="8" BackColor="red" Text='<%# Container.DataItem("ItemText") %>' /> <asp:Button runat="server" id="btViewItemText" Text="View Proposed Changes"/> </EditItemTemplate> </asp:TemplateColumn> <%-- POSTEDBY; POSTEDDATE; ITEMPARENT; SORTORDER; ITEMRATING; MODERATED; JPTOREPLY --%> <asp:TemplateColumn ItemStyle-VerticalAlign="top" HeaderText="Various"> <ItemTemplate> <asp:Table CSSClass="TableStyle1" runat="server"> <asp:TableRow> <asp:TableCell>PostedBy: </asp:TableCell><asp:TableCell><asp:Label runat="server" Text='<%# Container.DataItem("PostedBy") %>' /></asp:TableCell> </asp:TableRow> <asp:TableRow> <asp:TableCell>PostedDate: </asp:TableCell><asp:TableCell><asp:Label runat="server" Text='<%# Container.DataItem("PostedDate") %>' /></asp:TableCell> <%-- COULD do this dynamically, finding the values directly from the DataSet - see above --%> </asp:TableRow> <asp:TableRow> <asp:TableCell>ItemParent: </asp:TableCell><asp:TableCell><asp:Label runat="server" Text='<%# Container.DataItem("ItemParent") %>' /></asp:TableCell> </asp:TableRow> <asp:TableRow> <asp:TableCell>SortOrder: </asp:TableCell><asp:TableCell><asp:Label runat="server" Text='<%# Container.DataItem("SortOrder") %>' /></asp:TableCell> </asp:TableRow> <asp:TableRow> <asp:TableCell>ItemRating: </asp:TableCell><asp:TableCell><asp:Label runat="server" Text='<%# Container.DataItem("ItemRating") %>' /></asp:TableCell> </asp:TableRow> <asp:TableRow> <asp:TableCell>Moderated?: </asp:TableCell><asp:TableCell><asp:CheckBox runat="server" Enabled="false" Checked='<%# Container.DataItem("ModeratedYN") %>' /></asp:TableCell> </asp:TableRow> <asp:TableRow> <asp:TableCell>JPToReply?: </asp:TableCell><asp:TableCell><asp:CheckBox runat="server" Enabled="false" Checked='<%# Container.DataItem("JPStillToReplyYN") %>' /></asp:TableCell> </asp:TableRow> </asp:Table> </ItemTemplate> <EditItemTemplate> <asp:Table CSSClass="TableStyle1" runat="server"> <asp:TableRow> <asp:TableCell>PostedBy: </asp:TableCell><asp:TableCell><asp:Textbox runat="server" width="100px" Text=&#03

Problem creating DataGrid Template Column programm

fantozunea

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