ConstraintException was unhandled by user code

jcooper0 · June 16th, 2010, 09:28 PM

I am following along in Professional ASP.NET MVC 2 creating NerdDinner and running into a problem.

I made the change in Code snippet 1-32.txt.

Code:

        //
        // POST: /Dinners/Edit/5
        [HttpPost]
        public ActionResult Edit(int id, FormCollection collection)
        {
            Dinner dinner = dinnerRepository.GetDinner(id);
            if (TryUpdateModel(dinner))
            {
                dinnerRepository.Save();
                return RedirectToAction("Details", new { id = dinner.DinnerID });
            }
            return View(dinner);

        }

When I run under the debugger, VS 2010 breaks at

Code:

_Title = StructuralObject.SetValidValue(value,false);

in the following code with the warning "ConstraintException was unhandled by user code"

Code:

        [EdmScalarPropertyAttribute(EntityKeyProperty=false, IsNullable=false)]
        [DataMemberAttribute()]
        public global::System.String Title
        {
            get
            {
                return _Title;
            }
            set
            {
                OnTitleChanging(value);
                ReportPropertyChanging("Title");
                _Title = StructuralObject.SetValidValue(value, false);
                ReportPropertyChanged("Title");
                OnTitleChanged();
            }
        }

If I continue to debug, the correct view appears as in Figure 1-89.

If I run, but do not debug, I do not get the warning.

What is going on? Shouldn't TryUpdateModel be catching this error? Is the warning appearing because TryUpdateModel is is catching the exception rather than my code? Is this a feature of VS 2010 that I want to switch off? If so, how?

Thank you,
Jeff Cooper

sbornia · July 14th, 2010, 07:59 PM

I'm having the exact same problem. Any ideas?

jcooper0 · July 15th, 2010, 02:04 PM

I did find that if I included the MVC/ASP.NET debugging binaries, this went away. I presume that is because the error was being handled by code that was not recognized by the debugger and once the appropriate binaries are loaded, the debugger detects the exception handler in the MVC library.

nlinus · July 28th, 2010, 04:21 PM

I just started without debugging. Worked fine.

jcooper0 · July 28th, 2010, 04:36 PM

That works. I am just one of those people who wants all debugging turned on, likes to trace every line of code, and will not consider code to be complete until it generates no warnings. I know this is just sample code, but this is too much of an ingrained habit.

Compiling with the MVC debug libraries makes this go away. The issue is that if the exception takes place in a release binary and the catch is in the debugging binary, this error gets generated.

urban011 · August 3rd, 2010, 08:53 PM

I'm in exactly the same boat, and I share your concerns about running without a debugger. Did you ever find a satisfactory solution for this?

slink9 · August 8th, 2010, 12:51 PM

I run with the debugger on and just hit F5 to continue when the database errors come up.

adude28 · August 14th, 2010, 09:33 PM

Quote:

Originally Posted by jcooper0

Compiling with the MVC debug libraries makes this go away. The issue is that if the exception takes place in a release binary and the catch is in the debugging binary, this error gets generated.

I'm having the same problem. I'm a newbie so excuse my ignorance. If, I understand your solution ... you are saying that if I add the MVC debug libraries as a "Reference" to my project then everything works fine and you can still debug? Could you share how you added the MVC debug libraries to your project. I don't know where to find the binaries. Thanks!

ed

asdf · February 16th, 2011, 09:32 AM

Here is the solution:

Quote:

If you just want to debug against the provided DLL, you can install the symbols for System.Web.Mvc.dll. You'll be able to set breakpoints in the code, get better stack traces, etc. To do so, enter debugging mode then in the Debug menu, select Windows > Modules. Right click on the DLL in the Modules tab, the Load Symbols > From Symbol Servers. That'll download and install the symbols, and off you go.

-- http://stackoverflow.com/questions/1...vc-source-code

Load Symbols of System.Web.Mvc.