I am very confused right now. I have VS2008 at my job right now and I have a weird behavior that I have been searching for a while now.
When I compile the project, it works fine, but in runtime I have an error saying object not defined or something like that. The problem is that the imports/using is missing in my class but why does it compile?
In fact, I want to be able to see that error when compiling not when running the webapp.
REEDITED: Here is an example. Lets say i want to use a typed list, I am declaring my object list(of int) for example without having added my imports (system.collection.generic) in the class. then I compile, it works and then I run it, it fails because of the imports missing. is this normal behavior or not?
REREEDITED: I just noticed that the DLL of all my references were not copied in my bin folders even though all of them are set to "Copy local = true". Is it possible that it has to do with our shared directory (all external dlls) being on a network drive (\server\shared). I am really out of ideas on this issue....
problem was because we were having the classes in the app_data folder
The answer to the current question - why you are getting this error - is that ASP.NET does not show many errors at compile-time. You will need to manually go through the application to verify that all pages work correctly. This is very common with ASP.NET development, due to the nature of the environment.
If you post the real errors (probably should be as another SO question), we can perhaps help you with them.
Remove all the dll, etc from bin...
rebuild the whole solution then run
It should run fine...
Related
My question is similar to here: ASP.NET System.Anything is not defined
I am in the process of converting a website project to an MVC 4 project. To do this, I created a new MVC project and imported all of my content from the previous website. Both projects are in VB, and I'm using Visual Studio 2010 SP1, with both the MVC 4 update and TFS 2012 update applied.
I now have errors popping up when I build the MVC project. Things like "Type 'System.Web.UI.Webcontrol' is not defined." When I hover over the error, two of the prompts I get to fix it are
1) Change 'System.Web.UI.WebControl' to 'Global.System.Web.UI.WebControl'
2) Change 'System.Web.UI.WebControl' to 'WebControl'
Both of these seem to fix it, but does anyone know why I can't use "System.Web.UI.WebControl" to refer to this class? I'd rather not change all of my code... there are 100s of thousands lines in there.
Update: Outside of the System and System.Web.UI namespaces, I can also drop the 'System.'. So 'System.Drawing.Color' would become 'Drawing.Color'.
There exists another namespace containing System in your solution somewhere (e.g. Abc.System.def) - probably in a referenced library. After the conversion, the project file probably imported the prefix to System in said namespace (e.g. Abc), so when you type in System, it resolves to Abc.System.
I posted this question before I had whittled down as much of the compile errors as possible.
It appears that after I had removed all the System. references from the previous App_Code classes, the real errors started appearing. There were all sorts of messages about aspx controls not existing.
Ultimately, it seemed that I needed to right-click on the .aspx pages from my website project and choose 'Convert to Web Application.' This generated a .aspx.designer.vb file with the asp.net control declarations in yet another partial class.
After doing that for all pages, I am now able to use System. throughout the app.
To others who've asked, this System. error was only affecting the non-page code. .aspx, .aspx.vb, .ascx, .ascx.vb, .ashx, etc., files were not affected.
This does make some sense, anyhow, as I had previously pulled in all the App_Code libraries prior to pulling in the pages, and the site compiled. After importing the pages and their code behinds, the order of the errors was just odd. But I stuck with it and found the underlying cause.
Thanks for the willingness to help. If you have any other questions, I'd be glad to respond.
I am sorry if this is not really a coding question (it depends on if its my code causing the problem I suppose).
I have seen this question: Tracking down intermittent 'Object reference not set to an instance of an object.' error on build
However, it has not been of much help (although if you read the comments, you will see that I thought it did help for a while there).
When I try publish my website, occasionally, I will get an error with no file or line reference:
Pre-compiling Web Site
Building directory '/App_Code/'.
Building directory '/'.: Publication (web): Object reference not set to an instance of an object.
Pre-compilation Complete
------ Skipped Publish: Project X:\, Configuration: Debug Any CPU ------
I know the usual causes of "Object reference not set to an instance of an object" but this seems a bit different, isn't it supposed to be a runtime error? Not a build error?
What is weird is that it happens, seemingly at random (about 25%-33% of the time). I can try to publish it and have it fail. Then try again straight after, without changing anything and it works fine.
I started getting this error after moving some of my functions (VB.net btw) to a new file in the App_Code folder so they can be accessed by all pages of the site.
If you need any more info, please let me know.
Thanks,
EDIT: After further investigation, it seems to only happen if I try to publish the website within a few seconds of saving changes to any file within it. What could cause this?
The same error occurred for me to, I deleted the dlls of the custom controls in the web site that are already in the bin, then i published the web site, and succeeded
IF you have any custom/usercontrols in your project, they are actually running at design time and can give object ref errors. This can occur during builds too. In that case, a property is being referenced that is NOTHING and throws the error.
I had a similar problem with a Windows Form project.
Wherever I try to move a custom control on the windows form, and then try to save the form, VS2010 comes back with "Object not set to an instance of an object".
I suspected the error was deep down in the layers of abstraction in my inherited code, but couldn't work out how deep to go, without reviewing every line of code.
My solution to this problem is this.
Open up another instance of Visual Studio 2010
Menu: Debug | Attach to Process..
Search for "devenv.exe xxx YourApplicationName..." and select it
Click "Attach"
Menu: Debug | Exceptions..
Tick all the boxes in the thrown column, then "OK"
Your second instance of VS2010 is not debugging your first instance, including all the custom controls.
Return to the first instance of VS2010, and repeat the actions that caused the error in the first place, the second instance of VS2010 will break at the line of code that has the error.
You may want to look at this link there is a bug in vs2012
https://connect.microsoft.com/VisualStudio/feedback/details/749901/error-when-i-click-publish-object-reference-not-set-to-an-instance-of-an-object
I got strange compile-time error:
Project file must include the .NET Framework assembly 'WindowsBase, PresentationCore, PresentationFramework' in the reference list.
This project is aspnet mvc web application and all was fine for a long time.
After I added them Build went fine, but what could be a reason for this error?
It was caused by addition of file with .xaml extension.
By default, VS.NET try to complie it.
When I changed settings to BuildAction: none, copy to output: always I was able to remove those references.
i know that this error was solved, but in my situation, solution was different.
If you copied or moved an item from another project, its "Build Action" property might be set to "Page". This happened to me, and changing it to "Resource" or "Content" (because that's what the item was) fixed the problem.
You are using some type from the assemblies in your code. As a server side project this is almost certainly an error.
VS will normally give you an error immediately on entering the name of something for which it cannot find a definition so it seems odd that you got as far as a compile before noticing.
I could use some help trying to track down an intermittent error that I've been having with our ASP.Net project for quite some time.
Intermittently when building the solution, the build will fail with the error "/: Build (web): Object reference not set to an instance of an object." The error has no associated file, line, column or project information. The weird thing about the error is that it will go away on successive rebuilds and doesn't seem to result in any run-time errors that we've come across once the build is successful. Sometimes the error will pop only once, sometimes 3-4 times, but eventually the build will finish successfully and then seems to build just fine each time after. I haven't been able to nail down a pattern as to why and when the error will happen, and since it always eventually builds it hasn't been a critical problem for us. Just an annoyance. But one that I want gone for obvious reasons.
I guess I should add that this is an application that was originally developed in ASP.net 1.1 and converted to 2.0 and I inherited it somewhere down the line after that, so I don't know when the problem originally surfaced. As far as everyone here is concerned, it's always been there.
Obviously I'm not expecting someone to pick out the cause of my problem as that would require them to look at our entire solution to pick out potential problems. Just hoping someone can give me a couple fresh ideas as to how to go about tracking down the actual source of the error in code. It has to be coming from somewhere, right? How would you go about finding out where?
I've seen this when you have a web control in a page where there is invalid HTML. If your codebehind is trying to do something with the control, it won't be able to find it and will give you Object Reference... error at compile time. In my experience, it doesn't create a runtime error, and the project will build if the file in question is closed at the time of build. HTH, Good Luck!
Run this command at the command line and see if you get some more detailed information
%WINDIR%\Microsoft.NET\Framework\v3.5\msbuild.exe YourSolution.sln /v:n
To follow up on this problem, we never did track down the origin of the error but it disappeared when we upgraded to Visual Studio 2008 and converted the project to a Web Application.
The first thing I'd try would be to increase the compiler verbosity. This can be set in the Visual Studio options - e.g. "Tools->Options->Projects and Solutions-Build and Run->MSBuild project build output verbosity" for VS2005. If you set it to diagnostic then it should tell you what it's doing at the time the exception is raised at the very least.
I had this problem for a long time and finally found a solution that work fine for me.
It doesn't make sense to me... but altering my web.config file with the following gets definitively rid of this intermittent build error :
<buildProviders>
<add extension=".rdlc" type="Microsoft.Reporting.RdlBuildProvider, Microsoft.ReportViewer.Common, Version=9.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"/>
<!-- add this line below -->
<remove extension=".rdlc"/>
</buildProviders>
Hope this help !
I had this at build time when my project contained custom datasources (my own objects returning collections) with compile errors (that is, my objects had errors).
You'll also get this error if you try and add a datasource and your project doesn't have any datasources in the project's root (e.g. if you've put all your datasource classes in a subfolder). The only solution I found was to create a datasource in the project's root.
Sorry not to be more precise, but there seems to be several things that can go wrong with datasources/objects at compile-time.
An "Object reference not set to an instance of an object" is clearly a run-time error, not a compile-time error. So what that says to me is that Visual Studio is choking on something, which may not necessarily be in your code, or which something in your code is only indirectly causing.
Next question I'd ask: Does this happen only in Visual Studio, or does the same thing show up when you build using MSBuild or CSC?
What's really odd is that it's a run-time error. You shouldn't see that at compile time. Do you have any pre- or post- build steps attached to the solution? Any unit tests you're including with your 'build' process?
Where does this error show up?
Check the Application Log of your Event Viewer - It should tell you where the exception is being thrown.
Just to clarify, is it the compiler itself that is choking? Are you doing anything weird with #define and #if directives in your code? Maybe something is being done out of order at some point... Just a thought...
See if there are any post-build events that could be failing. These can be found on each project's property page.
Try using Rebuild Solution instead of Build Solution. You may need to add Rebuild Solution from Tools > Customize. If your web app installs or registers any windows services, and those services are started, Rebuilding plows through those types of problems.
OK, this begins to drive me crazy. I have an asp.net webapp. Pretty straightforward, most of the code in the .aspx.vb, and a few classes in App_Code.
The problem, which has begun to occur only today (even though most of the code was already written), is that once in a while, I have this error message :
Error BC30002: Type ‘XXX’ is not defined
The error occurs about every time I modify the files in the App_Code folder. EDIT : OK, this happens also if I don't touch anything for a while then refresh the page. I'm still trying to figure out exactly how to trigger this error.
I just have to wait a little bit without touching anything, then refresh the page and it works, but it's very annoying.
So I searched a little bit, but nothing came up except imports missing. Any idea ?
I think I found the problem.
My code was like that :
Imports CMS
Sub Whatever()
Dim a as new Arbo.MyObject() ' Arbo is a namespace inside CMS
Dim b as new Util.MyOtherObject() ' Util is a namespace inside Util
End Sub
I'm not sure why I wrote it like that, but it turns out the fact I was calling classes without either calling their whole namespace or importing their whole namespace was triggering the error.
I rewrote it like this :
Imports CMS.Arbo
Imports CMS.Util
Sub Whatever()
Dim a as new MyObject()
Dim b as new MyOtherObject()
End Sub
And now it works...
This happened to me after I added a new project to an old solution. I lowered the Target framework to match that of the other 'older' projects and the error went away.
Sounds like a pre compile issue, particularly because you mention that you get the error and then wait and it disappears. ASP.NET may be still in the process of dynamically compiling your application or it has compiled the types into different assemblies.
With dynamic compilation, you are not guaranteed to have different codebehind files compiled into the same assembly. So the type you are referencing may not be able to be resolved within its precompiled assembly.
Try using the "#Reference" directive to indicate to the runtime that your page and the file that contains your type should be compiled into the same assembly.
# Reference - MSDN
Check for a compiler warning (Output window of Visual Studio) "warning : The following assembly has dependencies on a version of the .NET Framework that is higher than the target and might not load correctly during runtime causing a failure". This happens when one of your dlls is compiled with a newer version of dotnet. If your current project is set to use a lower version of dotnet, the dependency chain prevents the dll (with the higher dotnet ver) from loading. It gives a compile error in Visual Studio, but can still run in IIS.
Sounds like it happens every time the website spins up (the app gets recycled every time you touch app_code and probably you have IIS configured to shut down the website after X minutes of inactivity).
I bet it has something to do with the asp.net worker process not having the correct access rights on the server. So its trying to load an assembly and is being denied.
Check this link and Table 19.3 for a list of all the folders the worker process account must have access to in order to function. And don't forget to give it rights to all files and folders in your virtual directory!
Replace your vbproj and vbproj.user file from your backup before if the references are equal