Get cannot find the master page error - asp.net

I have added master page to the project. Although I can successfully run the page, it doesn't switch to design view.
It gives me errors :
1)Cannot find the master page.
2)No build providers specified for the extension (They are added in both the applications and machine's web.config).
3)Can't switch to design view. Get an error cannot find a User Control. The UserControl is an dll, provided by the client for searching employees.

Just Clean the Solutions of Project.And Buid the Application.Again Re-Build the Application.
Ctrl+Shift+B --> To Build an Solution
Go to Build --> Clean Solution
Some times the Visual Studio get the intellisense problems.This is may also Like that i think otherwise there is nothing.

Related

MVC conversion project, fully qualified classes are not available unless 'Global' is added or System... is removed

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.

What makes an ASP.NET project an application vs library?

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.

How to convert ASP.NET website to ASP.NET web application

I have an ASP.NET 3.5 Website (visual studio lingo), but the site continues to grow and is looking rather cowboyish among other things. I'd like to see this get converted into a Web Application (namespaces and all).
Is this something that can be easily done in Visual Studio? If not, are there any other tools out there that could create all of the namespaces, etc. automagically?
Well, it turns out that the option "Convert to web application" does NOT exist for "websites". The option "Convert to web application" does exist only for "web applications" !!!!
[emphasis mine]
So, here's the deal, to do the
conversion, you need to:
Add a new "Web Application" to your VS 2008 solution (File->Add->New
Project->C#->Web->ASP.NET Web
Application).
Afterwards, you copy all the files in the old "website" to your newly
created "web application", and
override any files created in it by
default
The next step is the most ugly, you need to "manually" add the references
in your "website" to the new "web
application". I thought the VS 2008
PowerCommands toy would do this for me
as it does copy references from other
project types, but it didn't. You have
to do it by yourself, manually, and
you have to be cautious in this step
if you have multiple versions of the
same assembly (like AJAXToolkit in my
case) or assemblies that have both GAC
and local versions or so.
Keep repeating the last step and trying to build the "web application".
You'll keep getting errors like "
'....' is unknown namespace. Are you
missing an assembly reference? ". Make
sure you have none of those except the
ones where '....' is replaced by the
IDs of the server controls you use. In
other words, keep adding references
and building the project until only
the errors that exist because of
missing .DESIGNER.CS or .DESIGNER.VB
files.
Afterwards, go to the "web application" root project node in VS
2008 solution explorer, and right
click it, then you WILL find the
option "Convert to web application".
What this option does is actually
making small changes to the "#Page"
and "#Control" directives of pages and
controls, and creating the required
.DESIGNER.CS or .DESIGNER.VB files.
Try building the "web application" again. If you get errors, see what
references may be missing and/or go
click the "Convert to web application"
again. Sometimes, if there's any error
other than those caused of missing
DESIGNER files, not all the
pages/controls will have those
DESIGNER files created for them.
Fixing the non DESIGNER problem and
clicking "Convert to web application"
again should do the job for this.
Once you are done successful VS build, you should be ready to go.
Start testing your web application.
Optionally, you can right click the
"web application" root project node in
VS 2008 Solution Explorer and click
"Properties" then go to the tab "Web"
to set the "web application" to a
virtual folder in IIS (you can create
new virtual directory from there in
VS). If you want to use the IIS
virtual directory that the old
"website" used, you need to remove
that from IIS first.
Update: When testing your pages, pay MOST ATTENTION to classes in
"App_Code" folder, especially those
with NO NAMESPACE. Those can be a big
trap. We had a problem with two
extension method overloads in the same
static class that had no namespace,one
extends DateTime? (Nullable)
and calls another overload that
extends DateTime itself. Calling the
other overload as extension method
passed VS 2008 compilation and gave us
a compilation error ONLY IN RUNTIME
(With IIS). Changing the call to the
other overload from calling it as
extension method to calling it as
normal static method (only changing
the call in the same class, calls from
other classes remained extension
method calls) did solve this one, but
clearly, it's not as safe as it used
to be in VS 2005. Especially with
classes with no namespaces.
Update2: During the conversion, VS 2008 renames your "App_Code" to
"Old_App_Code". This new name sounds
ugly, but DO NOT RENAME IT BACK. In
the "web application" model, all code
will be in one assembly. In runtime,
the web server does not know what web
project type you are using. It does
take all code in "App_Code" folder and
create a new assembly for it. This
way, if you have code in folder named
"App_Code", you'll end up with RUNTIME
compilation errors that the same types
exist in two assemblies, the one
created by VS, and the one created by
IIS / ASP.NET Development Server. To
avoid that. leave the "Old_App_Code"
with the same name, or rename it to
ANYTHING EXCEPT: "App_Code". Do not
place any code in such "App_Code"
folder and prefereably do NOT have a
folder with such name in your "web
application" at all.
I know this since before but forgot it
now as I have not used "website" model
for long :(.
Walkthrough: Converting a Web Site Project to a Web Application Project in Visual Studio at MSDN
If your website application grows.. it's better to split it into several projects. Conversion from Web Site project to Web Application project won't help much.
If you're having problems getting your new Web Application Project to build check the File Properties in Visual Studio of all 'helper' classes. For a project I was converting the Build Action was set to Content whereas it should have been Compile.
I've now successfully migrated one Website project to a web application and there is quiet a few gotchas to look out for.
Having ReSharper at your disposal helps a lot in refactoring the aspx files.
Set up your solution and create an empty WebApplication
Copy all file over
aspx files in website projects don't have a namspace. Wrap your classes in the appropriate namespaces
During copying, all my pages in subfolders got renamed to my project name and the foldername, so I got 40ish public partial class FolderName_Projectname : Page If neccessary rename all files using Resharper or manually.
If you encounter multiple errors like "There is already a member Page_Load() defined", this is most likely due to incorrect class names und duplication
After adding a namespace
Replace CodeFile in all aspx pages with Codebehind and especially pay attention to files i your subfolder. Make sure Inhertis="" doesn't contain the relative path. Your namespaces take care of everything. So the correct format is Inherits="Namespace.classname".
If your class has a namespace NaSpa and a filename foo.cs it would be Inherits="NaSpa.foo"
After you have prepared all your files (don't forget your master pages), run "Convert to web application". If you encounter errors afterwards, rinse and repeat.
If you encounter errors of the sort "TextBoxName can't be found are you missing a reference", make sure you did not forget to sanitize your aspx pages. A good indicator is to check the automatically generated designer files. If TextBoxName does not appear in there, the conversion did not succeed completely.
Resolve any missing dependencies.
Build
Create a New Web Application in VS 2010.
1. Using Windows Explorer copy all your files into you project folder.
2. In VS 2010 solution explorer show all files.
3. Select the files and folders - right click include in project.
4. Right click the project solution explorer and select Convert to Web Application.
There are quite a few small differences, such as the App_Code folder will get renamed to old_app_code - that surprisingly doesn't cause any errors. The TypeName on your object data sources and the inherits on the #Page tag might need the [ProjectName]. prefix appended globally. For example if your type name was "BusinessLogic.OrderManager" and your project name is InventorySystem you would need to change it to InventorySystem.BusinessLogic.OrderManager. Also a few display changes, such as required field validators don't default to red font anymore, they default to black.
I was facing the same problems initially. After following the Wrox Professional ASP.NET 4.0 book, I found the following solution for my case.
I first created a new web application. Copied all the website files into the web application folder. Right click on the application, and click conver to web application.
You might ask why you need to convert a web app into a web app. The answer is, that when you create a website, you simply code the .cs file where-ever required.
A web application, however declares .design.cs (or .vb) and a .cs file for the code and design section automatically.
NEXT: Remove all manual references, like 'Inherits' attribute in the PAGE directive, to other files in your website, since name spaces WILL take care of referencing the classes centrally.
I also faced a problem, since I had not included OBJ and BIN folder in my project.
If you think you are missing your BIN and OBJ folders, simply click the 'Show All Files' icon in the Solution Explorer and then right click on the missing folders and add to project. (to make sure they compile with the project.)
UPDATE:
As #deadlychambers points out in the comments: You can search everywhere by doing a "Ctrl + Shift + F" and then search for Inherits="(.*?)". This will find all occurrences and probably save you some time!
the default ASP name space does not seem to work anymore. So I cannot seem to call my User Controls.ascx pages from outside the page. Giving them a namespace and changing the default from ASP to my namespace seemed to work.

Can Microsoft Code Contracts be used with an ASP.NET Website?

I'm currently using Microsoft Code Contracts in an ASP.NET MVC application without any issues but I can not seem to get it quite running in a basic ASP.NET Web site. I'm not entirely sure it was made to work with this type of project (although it shouldn't matter) so I wanted to bring it up to everyone.
I can compile the contracts just fine but the code skips over them since I'm assuming it hasn't been enabled through the Properties Page like you would do in other project types (ie ASP.NET MVC). I've gone to the property page of the project (which displays a dialog instead of the typical properties page) in my ASP.NET web site but it does not yield the same menu options and as such, doesn't have a section devoted to Code Contracts.
Also, I have Microsoft Code Contracts properly enabled within a class library project that I use to separate my business logic from the web site. The contracts compile fine but when a contract is violated, it throws a rather uninformative "Exception of type 'System.ExecutionEngineException' was thrown" error with no inner exception. My contract specifies a message to display upon violation but it is nowhere within the exception. It simply halts the execution of the process (which I believe is the default functionality for Microsoft Code Contracts).
I can't find anywhere that explicitly states that a particular project type can or can't (or shouldn't) be used with Contracts so I just wanted to see if anyone has had this issue.
Thanks for any help!
I had the same problem and this is how I solved it:
In the Referenced Class Libraries, right click -> properties -> code contracts.
Make sure "perform contract checking" is checked. I had mine set to "Full"
Contract Reference Assembly: make sure it is set to "Build"
Save your changes.
In the Referenced Class Libraries that have no contracts in their code, set the Contract Reference Assembly to "Do Not Build".
Then in the MVC project, have the Code Contracts "perform contract checking" checked. I had mine set to "Full".
Hope that helps somebody.
This sounds less like a Contracts and more like a build/config issue. Have you tried to deploy a prebuilt website? Are you sure that your website code sees the contracts code? Is the ASP.NET runtime using the CLR 4.0, or does it see the earlier Microsoft.Contracts.dll? Etc.

Casting error in ASP.NET

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?

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