I've recently started using a private NuGet server to manage my organization's internal libraries. This means in order to step into our own code that is in a library, I need to disable "Enable Just My Code" in debugging options since we aren't referring to the projects directly any more. This is a pretty hefty MVC project that uses dynamic types and ExpandoObjects in addition to ViewBag. I get two RuntimeBinderExceptions for every single use of a dynamic type... which is a lot. This appears to be normal behavior from what I've read. Normal it may be, but useful it is not.
My first thought was to disable this particular exeption in the Debug-> Exceptions dialog. The exception is not to be found there. I can't figure out any way to be able to step outside the projects referenced directly, without also opening myself up to these exceptions. (And all manner of other low-level framework exceptions that I don't want to hear about, but this is the biggest offender by far).
What's the best way to deal with this?
Edit: This is the problem. How do I stop this with "Enable Just My Code" disabled?
You can add additional "exception" names (existing in your own code or other libraries)...so long as you know the exception's fully qualified type name.
Managing Exception with the Debugger
https://msdn.microsoft.com/en-us/library/x85tt0dd.aspx
In Visual Studio 2010
Via the Debug | Exceptions... dialog.
Use the Add button to add a new exception under the Common Language Runtime Exceptions group and call it Microsoft.CSharp.RuntimeBinder.RuntimeBinderException
then just make sure Thrown and User-Handled are NOT ticked - thus causing the first chance exception to be ignored, rather than being caught by the debugger.
In Visual Studio 2017
Via the Debug | Windows | Exception Settings... panel
Use + to add the new exception name
make sure it's unticked
Related
I have a WPF application that has started failing with the following error at start:
System.InvalidOperationException: ''{DependencyProperty.UnsetValue}' is not a valid value for property 'BorderBrush'.'
This exception was originally thrown at this call stack:
[External Code]
This is not very forthcoming about what has caused the error. I have tried turning on the CLR Exceptions and restarting as per This Page, but it did not give any more information; I turned on the disassembly, but don't understand what it means. Turning on "Just My Code" debugging and all the Exception Settings as per this page got slightly more in the exception stack trace:
System.InvalidOperationException
HResult=0x80131509
Message='{DependencyProperty.UnsetValue}' is not a valid value for property 'BorderBrush'.
Source=WindowsBase
StackTrace: at System.Windows.DependencyObject.GetEffectiveValue(EntryIndex entryIndex, DependencyProperty dp,
RequestFlags requests)
This exception was originally thrown at this call stack:
System.Windows.DependencyObject.GetEffectiveValue(System.Windows.EntryIndex, System.Windows.DependencyProperty, System.Windows.RequestFlags)
but none of this gives me (that I can see) any information about what code is failing. I have got down to deleting various bits and re-starting the app, but it is extremely time-consuming and I can't help but wonder - is there something else I should be doing.
Is there any way I can find out which bit of code is failing, or any clues (e.g. search terms to look for in my code, clues as to whether it would be a .xaml or a .cs page, places to look in the Exception details, anything) that might help narrow down the location? For instance, is this something that would only be returned by a failed attempt to override the template defaults in wpf, or might it be caused by one of my windows - Is it likely to have come from a style maybe?
Basically, other than seeing that there seems to be a place where I should be setting the BorderBrush and am not, I have no idea how to find what error I need to fix - and since it is a missing thing, I don't know how to find it. Any leads, hunches or advice will be greatly received!
This is a WPF Windows Application, writing in Visual Studio 2019 using .NET 4.8
So it turns out that there really is no way to find out clearly where the error was, but through a process of deleting files, clearing out references and reinstating, I was able to find the problem.
There was a reference to a static resource in a connected .DLL that no longer existing since the .DLL was republished without checking. The change in name there meant that a resource was not found and the unset value was sent to the Dependency Property. It would be lovely if Microsoft were able to provide some sort of check on the location of problematic resources.
Here is my problem. I am a very big fan of Design by contract, I am using this concept especially when developing libraries that can be used by other developers. I just found out a new way of doing this which is: Contract.Requires instead of Exception:
So instead of having:
public void SomeMethod(string name){
if(name==null) throw new NullArgumentException("Null values not supported");
}
I now have:
public void SomeMethod(string name){
Contract.Requires(name != null);
}
EDIT: I am working under VS2010 on debug mode.
Problem: Contract.Requires does not do anything, even when name is null!
The MSDN documentation says:
Specifies a precondition contract for the enclosing method or
property.
But nothing is specified in case the condition is not met!
I also noticed there are other Contract.Requires overloads that throw exception, display message... but then what is Contract.Requires(Boolean) for?
EDIT Answer below highlighted that a plug-in must be installed to have the full power of Contract API but then what about Mono users who want their code to behave the same on different platforms?
You should do the following:
Install the Code Contracts add-in as nfechner has noted
Go to the project properties, 'Code Contracts' folder
Check 'Perform Runtime Contract Checking'
Switch 'Assembly Mode' to 'Standard Contract Requires'
Substitute your Contract.Requires with Contract.Requires<SomeException> (the first one throws System.Diagnostics.ContractException while the second throws the exception you specified which is important for public methods)
That's the basic setup. For more accurate configuration, refer to the manual
If you use Mono, probably, Contract class is empty. I haven't done this, but chapter seven from the Contracts manual seems to explain how to provide your own implementation.
From the Contract class docs:
Important
You must install a Visual Studio add-in to enforce contracts. The Code
Contracts Premium Edition add-in lets you specify static and run-time
checking of code contracts on the project Properties page. If you do
not enable run-time checking, contracts such as the Contract.Ensures
method will not throw exceptions during run time if a contract is
violated. The Visual Studio add-in does not ship with Visual Studio
2010 or the Windows SDK.
With a message like this it is usually helpful to specify exactly what you have done.
For example, you do not mention in the original message if you have installed the VS Addon, nor that you have enabled it under your project properties, or that you are actually running in debug vs release mode, etc.
Re Contract.Requires vs Contract.Requires<Exception>
Contract.Requires is recommended.
According to the manual
If your code must throw a particular exception on failure of a
particular precondition, you can use the generic overloaded form
below. (Please read Section 5.1 before committing to this form in your
code. You cannot use Requires < Exn <Exn>> without running the contract tools
on all builds. If you do, you will get a runtime failure everytime.)
I have a number of Contract.Assert statements in my code. When in Debug Mode, the assertions that fail throw an assertion failed dialog.
There are two things I don't understand about this:
Are Contracts not controlled by the Rewiter? So I thought if that it was unchecked, that no Contracts would be enforced. If this is not the case, what is controlled by the Runtime checking checkbox? What is not?
Why is an Assertion dialog thrown? They seem kind of useless, as in Silverlight, all I get is a IE dialog saying that an assertion has failed. I would prefer an exception.
Greg
The Contract.Assert method is also enabled under DEBUG, that's why you get the failure. Under Release, you should not see it.
If you want something other than the dialog, you need to either enable the rewriter, or register a handler with the ContractFailed event handler.
1 - A Contract is a contract, he must be accomplished although if it´s not necessary why use contract? Maybe you could use null labels values in the contract.
2 - Asserting do exactly this, show for the developer there is something going worn, this is mostly used in development environment, when you put in production remember to build in release to exclude this validation from the IL .
Here is the error
Cannot evaluate expression because a thread is stopped at a point where garbage collection is impossible, possibly because the code is optimized.
I am writing a simple console app and the first line of code is this:
List<MyObjectModel> list = MyObjectModel.GetNonCompletedReturns();
and the code for the function is:
public static List<MyObjectModel> GetNonCompletedReturns()
{
MyObject service = new MyObject();
List<MyObject> entities =
(from recs in service.Retrieve() where select recs).ToList();
List<MyObjectModel> models = new List<MyObjectModel>();
foreach (MyObject entity in entities)
{
models.Add(BindModel(entity));
}
return models;
}
and if I try to step through the code, as soon as I get back to the main of my app and hover over the list, I get the error message that I showed.
Can anyone help?
If your project is compiled in release (with optimizations turned on), you may see this. Have you tried the DEBUG configuration?
This error fires only when you are trying to use Watch dialog during debug.
Try to use some other technique to output the variables, like Debug.WriteLine, Console.WriteLine and so on.
None of the answers solved my problem so I'm posting the solution that helped me.
"If there is to much data in the parameters then this error can occure,
a simple solution is to make an object, not a struct because that's a dataobject.
Put this object in your parameters instead of all the different variables,
normally the problem will no longer take place."
Here's a little trick just in case you want to examine some objects and you are not able to change the parameters:
I've created a call to a new temporary function, inside the function from where I was unable to watch my object. Then, inside that new function I was able to watch my object. After the job is done, just delete the function.
While it's true that the "Cannot evaluate expression because a thread is stopped at a point where garbage collection is impossible, possibly because the code is optimized" error appears when in release mode, most developers just ensure that their projects are configured to compile as a debug build. BUT to be sure that you have no release-DLL issues, you also must check the references to DLLs that are in your solution and make sure that you don't have a reference to a release-build DLL. If you find that this is the case, delete the DLL reference and then add a project reference rather than a DLL reference. The project reference will ensure that your solution references debug or release versions of the DLL as specified in your build configuration.
Note that the above advice applies, of course, to only those DLLs to which you have source code and which are built from a project in your solution.
I got this too, when I hit a NullReferenceException from a 3rd party control.
In this one case, I found that if I set a breakpoint before I hit the exception, I could then single step through the rest of the code without seeing the problem.
No idea why, but this worked for me - in this case at least.
For what it's worth, this error can also be caused by an infinite loop in a property getter (simplified version below). When the debugger attempts to evaluate the property (e.g. in the watch window) the UI will hang for a few seconds and the "Cannot evaluate expression..." error will appear for many of the other properties in the same class.
public int MyProperty
{
get
{
while (true) { }
return 0;
}
}
First make sure that you're running your code in DEBUG mode and with code optimization turned off. you can turn that off from the properties of your project.
If you made all of the above and the problem persists, then it's probably a problem with the stack having Debug.Break() on top of it. The solution for this is very easy, just press F10 to move to the next line and you should be able to evaluate the expression.
You can check this SO question for more information about this issue.
I was experiencing the same error message in the Visual Studio debugger when evaluating a linq expression.
Disabling the VS debugger config setting 'Enable Just My Code' resolved the issue for me:
To enable or disable Just My Code, choose the Tools > Options menu in
Visual Studio. In the Debugging > General node, choose or clear Enable
Just My Code.
https://learn.microsoft.com/en-us/visualstudio/debugger/just-my-code
I was having same issue in Visual Studio 2017. Going to Debug> Options> Debugging> General and checking "Suppress JIT optimization on module load(Managed only)" fixed my issue
I have my client calling a WCF Server I'm hosting locally, right now I'm debugging the client so on the server I'm purposely throwing a FaultException to see how the client would handle it.
The part that is annoying is that the debugger pauses on the line that throws the FaultException. How do I get it to NOT do that? I looked in Visual Studio's Options (Debugging) and don't see anything that resembles an option for this.
Use the DebuggerStepThrough attribute on the method you wish the debugger to skip over.
You can configure the debugger to ignore certain exceptions by going to "Debug -> Exceptions" (shortcut: Ctrl+Alt+E) and unchecking "user-unhandled" for the exceptions or their namespace.
Disable either System.ServiceModel.FaultException`1 For Typed FaultExceptions (FaultException< TDetail >) or System.ServiceModel.FaultException for both typed and untyped FaultExceptions.
Find both by searching for the words "Fault" with "Find ..." or by expending "Common Language Runtime Exceptions-> System -> System.ServiceModel"