Obj. reference not set to an instance of an obj.

magic_e · Apr 28, 2012

Hi I have a webcontrol table in a ASCX, I am trying to turn the table's visibility on and off in a VB file but I got an Error stated as above. There are 4 files involved. Can you please have a look at the code and see anything wrong. FILE 1 - error.ascx: <asp:Table id="tblErrors" Runat="server"> <asp:TableRow> <asp:TableCell> .................................... </asp:TableCell> </asp:TableRow> </asp:Table> ----------------------------------------------------------- FILE 2 - product.aspx: <%@ Page Language="vb" AutoEventWireup="false" Codebehind="products.aspx.vb" Inherits="project.products"%> <%@ Register TagPrefix="page" TagName="error" Src=http://aspmessageboard.com/archive/index.php/"./ascx/error.ascx" %> <form id="Form1" method="post" runat="server"> <page:error id="error" runat="server" /> </form> ----------------------------------------------------------- FILE 3 - product.aspx.vb: Imports project.CommonFunctions Public Class products Inherits System.Web.UI.Page Protected WithEvents tblErrors As System.Web.UI.WebControls.Table Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load pShowError(tblErrors) End Sub ----------------------------------------------------------- FILE 4 - CommonFunctions.vb: Public Class CommonFunctions Public Shared Sub pShowError(ByVal oTable As System.Web.UI.WebControls.Table) oTable.Visible = False End Sub The ERROR is pointing at "oTable.Visible = False". ThanksWhy didn't you initialize the Object: FILE 4 - CommonFunctions.vb: Public Class CommonFunctions Public Shared Sub pShowError(ByVal oTable As System.Web.UI.WebControls.Table) dim oTable as New System.Web.UI.WebControls.Table or if you "Imports System.Web.UI.WebControls" you can use: dim oTable as new table oTable.Visible = False End Sub Try this and it would work Hi Fadi, is this what U suggest ? Public Shared Sub pShowError(ByVal oTable As System.Web.UI.WebControls.Table) dim oTable as New System.Web.UI.WebControls.Table oTable.Visible = False End Sub It said "oTable already declared as a parameter of this method" Any idea ?Ok try to do thw following imports System.Web.UI.WebControls Public Function pShowError(ByVal as table) as boolean if oTable.Visible = False return 1 else return 0 End Function I suspect the cause of the problem is that the webcontrol table is in ASCX not in ASPX, therefore the CodeBehind of ASPX cannot find it, am I correct ? If yes how to solve the problem ? ThanksHi fadi, I have no luck getting it to work. What I have tried to do is to see if I can make it invisible in FILE3

roduct.aspx.vb, I am not calling the pShowError function in CommonFunctions.vb Public Class products Inherits System.Web.UI.Page Protected WithEvents tblErrors As System.Web.UI.WebControls.Table Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load 'pShowError(tblErrors) tblErrors.visible = False End Sub But the error points at tblErrors.visible = False saying "Object reference not set to an instance of an object". So I believe because tblErrors is in ASCX and not in product.aspx, that's why it doesn't work, Right ?Do you still get the errorSame error because the webcontrol is in ASCX and not ASPX which the code behind cannot find it, I still dunno how to access the webcontrol in ASCX

Obj. reference not set to an instance of an obj.

magic_e

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