is this possible?

carson · Apr 28, 2012

I'd like to have a datagrid with several template columns each with its own databound listbox. Each of these would then AutoPostBack on change and would update a bit of example text. The listboxes themselves would only have to be created on page load and would also be within an "if NOT isPostBack" statement. I've created a mock of this as can be seen here: http://216.87.15.155/datagrid.gif It seems like this must be possible, but everytime I attempt to bind my data to a listbox it says the listbox isn't declared (because it's within a template column of the datagrid i'm assuming.) Please say it's doable!

])ryHey Dry, Here are a few links that have some great code examples: http://www.dotnetjunkies.com/tutorials.aspx?tutorialid=77 http://www.dotnetjunkies.com/tutorials.aspx?tutorialid=86 I've had to bind controls within a datagrid, and I've been doing it from the html view, so if you're trying from teh code behind that may be the cause? Something to check out anyway Hope this helped.

JackBasically the listbox is one level deeper than the current variable area. Therefore you must declare a variable that references the listbox In the onItemDataBound procedure you need to declare a local variable for the listbox Public sub item_OnItemDataBound(sender As Object , e As System.Web.UI.WebControls.DataGridItemEventArgs) Dim ddlStates As DropDownList ddlStates = CType(e.Item.FindControl("ddlStates"), DropDownList) ddlStates.DataSource = ... THey T, I've tried what you suggested, but keep getting the following error when I attempt to set the dataSource: System.NullReferenceException: Object reference not set to an instance of an object. Here is what I've got for the sub: Public Sub bindLists(sender AS Object , e AS DataGridItemEventArgs) dim lstFF AS DropDownList lstFF = cType(e.Item.FindControl("lstFontFams"), DropDownList) dim FFComm AS new SqlCommand("SELECT styleFontFamID,fontFamily FROM wsStyleFontFams ORDER BY fontFamily", objConn) lstFF.DataSource = FFComm.ExecuteReader(CommandBehavior.CloseConnecti on) lstFF.DataBind() end sub And here is the dropdown: <asp

ropDownList id="lstFontFams" runat="server" DataTextField="fontFamily" DataValueField="styleFontFamID" AutoPostBack="True" /> Any ideas? Thanks, ])ry thanks jack, i'll definately check out the tutorials.I think you need to ignore the rows that arent in the dataset(header and footer) 'ignore row if it is not a datarow itemType = CType(e.Item.ItemType, ListItemType) If (itemType = ListItemType.Header) Or (itemType = ListItemType.Footer) Or (itemType = ListItemType.Separator) Then Return End If I have listed my complete onitemdatabound for you to see how I implemented it. The basic concept is for each item it can have multiple colors so I put the color in a drop down box, if it only has one color just show it as a label, and use set value of the dropdownlist to the sku which is what makes the item unique. Public sub item_OnItemDataBound(sender As Object , e As System.Web.UI.WebControls.DataGridItemEventArgs) Dim lblLPrice As Label Dim lblPrice As Label Dim pnum As String Dim size As String Dim price As Double Dim itemType As ListItemType Dim oUtil As Utility Dim MyList As DropDownList Dim lblColor As Label Dim MyItem as ListItem = New ListItem() oUtil = New Utility() 'ignore row if it is not a datarow itemType = CType(e.Item.ItemType, ListItemType) If (itemType = ListItemType.Header) Or (itemType = ListItemType.Footer) Or (itemType = ListItemType.Separator) Then Return End If 'set cell to no wrap e.Item.Cells.Item(0).Wrap="false" 'display price, display old price with a stirke through if it is greater than price lblLPrice = CType(e.Item.FindControl("lblLPrice"), Label) lblPrice = CType(e.Item.FindControl("lblPrice"), Label) lblLPrice.Text=System.String.Format("{0:c}", e.Item.dataitem("price")) IF e.Item.dataitem("list_price") <> e.Item.dataitem("price") THEN lblPrice.Visible=true lblPrice.Text = " " & System.String.Format("{0:c}", e.Item.dataitem("price")) lblLPrice.Text = "<S>" & System.String.Format("{0:c}", e.Item.dataitem("list_price")) & "</S>" END IF Dim description As String Dim prod As String description = e.Item.dataitem("description") prod = e.Item.dataitem("prod") pnum = e.Item.dataitem("prodnum") size = e.Item.dataitem("sz") price = e.Item.dataitem("price") 'build color display MyList = CType(e.Item.FindControl("MyList"), dropdownlist) Dim arParams(4) As SqlParameter arParams(0) = New SqlParameter("@param1", strUid) arParams(1) = New SqlParameter("@param2", size) arParams(2) = New SqlParameter("@param3", price) arParams(3) = New SqlParameter("@param4", description) arParams(4) = New SqlParameter("@param5", prod) MyList.DataSource = SqlHelper.ExecuteReader(ConfigurationSettings.AppS ettings("cnnString"), CommandType.StoredProcedure,"LS_Product_ListColor",arParams) MyList.DataBind() lblColor = CType(e.Item.FindControl("lblColor"), Label) If Mylist.items.Count < 1 Then 'throw error Else If Mylist.items.Count = 1 Then lblColor.visible="True" lblColor.Text = Mylist.items.item(0).ToString & "<INPUT TYPE=hidden runat=server id=sku" & e.Item.ItemIndex + 2 & " type=hiddden name=sku" & e.Item.ItemIndex + 2 & " value=http://aspmessageboard.com/archive/index.php/" & Mylist.items.item(0).Value.ToString & ">" MyList.visible="False" Else If Mylist.items.Count > 1 Then MyItem.Value = "none" MyItem.Text = "Select Color" MyList.Items.Insert(0,MyItem) End If End Sub .

is this possible?

carson

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