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.
Related
Ok, I am in the process of breaking apart of intranet application (VS 2010 Web Site, ASP.NET Web Forms with VB code behind). During this process i'm trying to convert some of our our app_code files in to WCF rest service in a new project. However, when I copy or "add existing" vb files into the new "services" project. I get tons of errors including...
error BC30002: Type 'XXX' is not defined
warning BC40056: Namespace
or type specified in the Imports 'System.ServiceModel' doesn't
contain any public member or cannot be found. Make sure the
namespace or the type is defined and contains at least one public
member. Make sure the imported element name doesn't use any aliases.
From what i've read it may (or may not) have something to do with Assemblies and references that I just have very little knowledge on. I have added the namespaces from the current web.config to new project's web.config, and the files are identical. So there is something in the background that needs to be added to the new project I just don't know what its.
PLEASE HELP!!
THANKS
JOSH
UPDATE 1
So one of the errors i'm getting = "error BC30002: Type 'MailMessage' is not defined." Which is a namespace that is added to the web.config, which apparently isn't being picked up??? IDEAS?
I've come across a similar issue - not sure what the reasoning behind it is, but I got around it by creating a new .vb class with the same name as the one you want to copy, then copy and paste all the text from the old one to the new one. Save it, then it seems to like it - it didn't like me copying and pasting the actual file, nor did it like me adding existing files.
Hope this helps :/
This issue seems to be tied to the the differences between Web Application Projects versus Web Site Projects. Eventually I had to add different namespaces on the new project level.
Here is more info about WAP vs WSP....
http://msdn.microsoft.com/en-us/library/dd547590(v=vs.110).aspx
To be more specific, when a cshtml is needed, what happens? I would need to build an application with only ashx and a template engine, without the MVC stuffs, simple rendering, but i would'not like to loose the capability to change the cshtml files on the fly. So I have somehow to manage their recompilation, possibly without recycling the application server loading and unloading AppDomains.
On the first request I can build the page and load it in a sort of cache (like RazorEngine on codeplex), then reuse it. When the page changes i should change the page and that's it.
But as far as I understood a new assembly is built for every page, so if there are frequent changes (that is likely to happens in my environment) tons of assemblies will get loaded.
The question is,
How it works for the standard MVC ?
CodeDom is used, or directly IL that is subsequently added without creating new assemblies?
One thing that comes me in mind now is that after building the assembly, it can be decompiled and then the IL loaded directly on the app, that would make sense
Ask for further clarification if it's unclear! (and any suggestion to this Stackoverflow newbie is welcome)
Ok,
First the cshtml files are loaded then the files are compild into their own assemblies with the standard CSharp/VbCodeCompiler, no code dom is present as far as i understood...
I am inheriting some ASP.NET code (I am an OS guy, not a web dev (yet ;-)). The solution has been re-factored and there are multiple projects (libraries and asp.net sites) in it. Aside from the libraries, there are two asp.net projects (called MAINSITE and SUBSITE). Only MAINSITE is being used as the official site (as an asp.net site), and MAINSITE has a depency on the code in the SUBSITE asp.net site, but doesn't use the site itself. I am trying to figure out how to clean this up and convert SUBSITE into a library.
My quick question is, whenever I debug the MAINSITE (set as default), it runs two asp.net processes: MAINSITE and SUBSITE. And so, at the very least, how can I avoid this? Is there a quick/temporary solution to this?
My detailed question is this:
What makes an asp.net site an asp.net site? For instance, in C the difference between an dll and exe could be defined (superficially anyway) as the presence of a main, and potential export information for the library (among other things, of course). If I were to convert an exe to dll I might:
1. remove the main code
2. make sure the public interface was correct (and exported correctly)
3. convert the makefile to build a dll rather than an exe.
Can someone point me to some similar steps for asp.net to .net lib?
Maybe:
1. get rid of index.aspx
2. get rid of web.config
3. any *.cs files to remove?
4. how do I change the properties?
5. any gotchas?
Thanks so much for your help.
Details: Visual Studio 2008/.NET 3.5
There are many, many components to make an application run as an ASP.Net application. However, in terms of your actual Web Application project, there's really not that much difference between it and generic library code except for the fact that much of your code relies on the existence of the HttpApplication runtime.
Any code that utilizes the System.Web (especially System.Web.UI) is going to be suspect in terms of having this dependency. For example, all the code in page or webcontrol event handlers (Init, Load, PreRender, etc.) relies on the fact that there is an HttpHandler (running inside an HttpApplication) raising these events. If you run the same WebControl out of a library that's not in an ASP.Net project, none of this will ever happen and the control will be useless. However, that exact same library would be quite functional if executed in the context of an ASP.Net process.
It really boils down to what process you're running the library in. In most cases, ASP.Net processes are spawned by IIS, although it is possible to host an ASP.Net process in other types of programs as well.
There isn't a simple 5-step process for converting a web project to a library unfortunately. But as a rule of thumb, webcontrols, .aspx and .ascx codebehind aren't going to convert.
For a more detailed look at what makes code into an ASP.Net program, see Rick Strahl's "A Low level look at ASP.Net".
If you go to "File" > "New" > "New Project..." and then click on the (assuming you're using C#) "Visual C#" in the list on the left, you're given the ability to create a "Class Library" project. You can extract all the relevant code to one of these and then reference in in your "MAINSITE".
You will need to reference it in the "References" section of your MAINSITE project and may need to import your library project using the import keyword.
I'm onto a real head scratcher here ... and it appears to be one of the more frustrating topics of ASP.NET.
I've got an assembly that implements a-lot of custom Linq stuff, which at it's core has zero web functionality. I have an additional assembly that extends this assembly with web specific behaviour.
The web specific behaviour comes with a couple of user controls marked up inside ASCX templated UserControls.
I'm having trouble putting a nice finish on this assembly so that it is simple to redeploy for use in other applications. Let me run through what I've tried so far:
Copied the ASCX files to the consuming web application using build events; far from ideal and quite a deployment nightmare.
Implemented a custom VirtualPathProvider and embedded the ASCX templates within the assembly as embedded resources. Unfortunately when using the Register directive in the consuming application it creates the designer declaration as a UserControl, where I would require a declaration of the actual control type; unforeseen (typically) and undesirable.
Created a Web Deployment Project to compile the UserControls, but the compiled user controls then become part of another assembly, and no longer descend from the class definitions in my web assembly--the assembly needs to instantiate them dependent on the request context.
So number 1 is just crap, number 2 doesn't give me the type support I desire and number 3 I think I'm about to produce a reasonable solution with:
Lump all non-control classes into the App_Code folder, prepare a factory class that will construct an object of the desired control type using reflection and the expectation that the type being reflected will be present in the deployment output (hopefully guaranteed by the presence of the ClassName attribute in the Control directive).
Theres also always the other option of rewriting the ASCX controls into custom controls, but just don't have the resources to consider it at the moment, and we've got no expertise in doing that, and they work fine as UserControls.
Am I missing something obvious, something maybe much simpler, or is this just purposefully difficult? I've read stories of the ASP.NET compilation process being very unfortunate in it's design on my travels across this topic.
Well I think I've done it ... by being mindful of a few of a few annoying pitfalls with my last approach, I recommend the following when compiling ASCX user controls in a Web Application Project using a Web Deployment Project:
Avoid putting classes in App_Code unless they're standalone or helper classes, ASP.NET treats this as a speshul folder, the meaning of which is lost on me, mayhem, confusion and chaos follows. Code in this folder does get output in the Web Deployment Project, though.
Pay close attention to your assembly names, their root namespaces and deployment output assembly name- you'll get access is denied errors if you have any naming conflicts during the aspnet_merge process.
Ultimately you'll most likely end up deploying 2 assemblies, I tried to create only one but the deployment output was still pointing to type definitions in the source assembly. This isn't a problem if you don't have any other types in your Web Application Project--I have so it was a problem for me. In my case, my final output was:
<Organisation>.<TechnologyName>.Web.DLL - Compiled Web Application Assembly (containing the ASCX templates)
<Organisation>.<TechnologyName>.Web.UI.DLL - ASP.NET Compiled UserControl assembly, created by Web Deployment Project
Clean often, and check that the Web Application Project's bin and obj paths are cleared of any previous junk built when you perhaps hadn't finalised your namespace or assembly naming scheme--the Web Deployment Project will be quite keen to include these, causing a fine mess.
Check your imported namespaces, the ASP.NET compiler likes to refer to the Import directive in the ASCX template, and it also considers imported namespaces present in web.config's <configuration><system.web><pages><namespaces> element, tweak if you get unknown definitions appearing during the deployment process.
Have some patience spare, it's quite tricky! But you do get some nice re distributable UserControls at the end of it!
Phew!
I have a class declared in the App_Code folder. The class contains a public shared method that returns a type Portfolio.
When I try to call this method to initialize an object of type Portfolio in one of the ASCX controls, i get a "Value of type Jaguar.Portfolio cannot be converted to Jaguar.Portfolio" message.
This is a "Website" project. I have tried using CType and DirectCast and I still get the same compilation error when I try to build the site.
I am using the line of code listed below in the code behind file of the ascx control
Dim pObjSvc As Jaguar.Portfolio = ClassName.GetPortfolio
Do you have a webpage or a user control also called Portfolio? You may have a name space collision where it's confused between which Portfolio object to use. If this is the case, you'll need to change the name of the Class/Module or the control's or page's code behind class and you should be all set.
There seems to be someone else with the same problem out there:
ASP Net - value of type "MyNamespace.MyClassName" cannot be converted to "MyNamespace.MyClassName"
I have a ASP.Net application that uses
assemblies from several other
solutions. When testing the
applications on my machine I build all
the referenced assemblies using nmake.
The latest assemblies get placed in a
common directory that is referenced by
my ASP.NET app.
Occasionally I receive the following
error: value of type
"MyNamespace.MyClassName" cannot be
converted to "MyNamespace.MyClassName"
(there are a lot of these for
different classes) when doing a debug
build. I have tried the following with
no luck:
Build the ASP.Net application Rebuild
the ASP.Net application Close VS and
build the ASP.Net application Close
VS.Net as rebuild the asp.Net
application IISreset and build/rebuild
the application
It seems the only thing that works is
if I run nmake to build all my referenced assemblies, I can then
build the ASP.Net application.
Any ideas as to what causes this? Is
there an easier way to fix it?
Sadly, the author of the question did non find a definitive answer. But perhaps it contains a hint which could be helpful to find the solution.
UPDATE: I'm not sure if that is even possible in a ASP.NET website, but maybe you accidentally added a reference to a (temporary) assemmbly of the project itself? That would explain the error. Try also to remove the contents of bin and obj folder.
Just a debugging tip:
Try to rename the Portfolio class and recompile. Maybe there is an old assembly somewhere or some other code in .vb your files which contains a class with the same name?
I have seen situations similar to this when an aspx page was created with the same name as a business object class. Do you have some some aspx page with a code-behind class of Portfolio as well?