object reference not set to an instance of an object

[thersitz]

Hi,

Very new to asp.net. Using VStudio 2005 on an XP Pro machine. Using Cassini
to view.

I see this error discussed all over the net but don't seem to find a way to
resolve my particular grief -- which I am sure is not unique. Here are my
basic steps:

1) create a masterpage -- add some simple graphics to the header.
2) add a new web form that references the master page and attaches a code
behind file. (actually added 3 files referencing the same mpage -- each
errors)
3) add some basic html into the placeholder auto-created in the web form
page, ie:

<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1"
Runat="Server">

</asp:Content>


4) view the page and it all views okay.

But when I look at the page in design mode -- the Content placeholder shows
this error -- and it is referenced in the error list as well.

================
Error creating control - Content1
object reference not set to an instance of an object
================

Can anyone give me a heads up as to what this error means, how to get rid of
it, etc. I am guessing that it wants me to declare an object -- but where
(assuming codebehind file) and I am wondering why vstudio doesn't auto do
it? - which makes me think my guess is wrong.

thanks

 

[Jon Paal]

save your project , close out and reopen, that usually clears that problem up for me.

 

[thersitz]

Thanks Jon. I saw that suggestion in one of my google returns and tried
it -- but to no avail.

I've been playing around a bit and have noticed that this error does not
show until I paste in some basic html. I am going slowly into this aspNet
thing and am still using some traditional html -- div, p, table -- as i get
a feel for vstudio etc -- not using the html controls.

So my html is producing the error -- but why?

 

[thersitz]

Well I have narrowed the source of the error to this piece of code:

<!--#include file="imageBar.inc" -->

So I just need to come up with an aspnet version of this code.

thanks

 

[David Wier]

Try just running that piece of code by itself (copy it to a blank web page)
It sounds like something in particular on that page might be causing the
problem.

 

[David Wier]

Try just running that piece of code by itself (copy it to a blank web page)
It sounds like something in particular on that page might be causing the
problem.

 

[Tom]

I am having the same issue. I have a master page with one editable region. When I use the master and place plain html 4.0 data in the editable region it creates this error while in design view. Error Creating Control - Content1 Object Reference not set to an instance of an object.

The page renders correctly and build correctly. I have restart and tried various data. Is it becuase I am creating the page in another folder other than the master page. Even though it is looking for web root is it confused?

The page directive looks like this:

<%@ Page Language="C#" MasterPageFile="~/public/Public.master" >>> The rest is normal stuff.

My Directory structure is:

/
/public
/public/info
/public/news
/public/...more folders

my master is in /public/Public.master

The pages I am having issues in are the subfolders

/public/info/page_one.aspx

The files in the same folder as the master works fine:
/public/public.Master
/public/Default.aspx

Thanks

EggHeadCafe.com - .NET Developer Portal of Choice
http://www.eggheadcafe.com

 

[mike]

you may find the answer here.

http://odetocode.com/Articles/450.aspx

Mike