In resharper is it possible to force an update of an interface?
Basically I have a class that inherits from an interface but this class is constantly changing so I need to reflect the changes in the interface otherwise VS complains that I am not implementing something as the signature of the method has changed.
I was wondering if there is a way in resharper to say "Update this class with its interface" ?
Any ideas?
Although not the best way to design, sometimes it is necessary to update the interface based on the modified class.
You can update the interface using resharper's Pull Members Up option.
Use the Pull Members Up option in the refactor menu
Select the interface you would like to update as the base type
Select the members you would like to add to the interface
The members have now been added to the interface.
If you use ReSharper to modify the method, it can/will also modify the interface definition.
For instance, if you use ReSharper's Rename functionality on the method, the interface definition of it will get renamed. Additionally, if you use ReSharper's Change Signature functionality on the method, it asks you if you want to do the refactoring on the interface as well.
If you're changing signature of a method defined in an interface, change it via Refactor - Change Signature.... ReSharper will then ask you if you want to change signature of an interface method.
Other than that, I cannot imagine how would ReShaper know what and how to update.
Letting the interface follow the implementation is the exact wrong direction. First, you should define in your interface, what you need, then implement it in the backing class. You shouldn't expect a tool to support undesired workflows instead...
If you go the right way, R# will give you all support you ever need: You can refactor existing methods via Refactor|Rename..., Refactor|Change Signature... and Implement Members.
Related
I'm trying to find out if there's a way to stop functions/methods from being added (EDIT: by other developers) to a class for the case where the object is a Model or DTO which should not contain methods (to prevent 'abuse' of the Models/DTOs by others, who may try and add 'helper' methods etc).
Is there any way to achieve this?
Use reflection and write a unit test that fails if a model-class has methods.
Mark all you model classes with a custom attribute. Then make a unit test that uses reflection to load a given assembly, iterate all classes in that assembly and check that classes marked with the model attribute does not have methods. This should be fairly straight forward using reflection.
I believe you are trying to solve a procedural issue with code where you should be using communication.
Your colleagues (i assume) are operating on the code files with 'full trust' privileges. If they break that privilege you should open a dialogue. Use the change as an opportunity to educate them on the intended design. Perhaps they are correct and you will be educated!
I suggest simply making the intended design obvious in the class name and with a comment stating the intended nature. Perhaps quote the design document(s) that informed the class.
You cannot hinder anyone with full write-access to your code-base to do so. The only two things you may do to avoid it are create some CodeAnalysis-rule for FXCop as mentioned by Christian.K in the comments or by writing your DTO-class so that it is undoubtly a DTO that should not have any methods by using a unambigious name for the class and if this is not enough provide some code-comments that notifies the coder to do not so.
However you may need some kind of method if using collections e.g. where you will need some kind of comparision if two instances of your DTO are equal, so you have to provide at least an Equals- and GetHashCode-method.
You don't need to use a struct to prevent additions to a class. You can use the sealed keyword
public sealed class MyDTOObject { ... }
Now, you can not inherent a class and also prevent inheritance (which is essentially what you're asking). The very fact of inheriting MyDTOObject is creating a new class which is based off of not equal to, or restricted, or defined in any way by the implementation of MyDTOObject.
You can use an abstract class, to force derived classes to implement certain methods, but not the other way around.
If you want to prevent others from deriving from your class and implementing helper methods, you must use the sealed keyword, or mark the class internal.
You may prevent the class being extended or inherited by marking it final that way nobody would be able to extend your class and hence not being able to add any behavior. But stop and ask yourself whether you want to do that or not, because then you'd be signing an invisible contract that everything ever required by the class is written in the class and this class needs no further addition.
To be clear, I was talking in Java context.
Situation:
I implement an interface implicit and remove a property on the interface (later).
There is no warning that this property should be removed on the implementation class.
I know I could implement the interface explicitly, but I would try to go around that.
EDIT: (added a question)
How can I be notified/warned/... that I maybe no longer need the member in the implementing class?
There is no way the compiler can give you such a warning in C#. It would somehow need to have knowledge of past versions of the interface to know what method/property was removed and therefore identify possible candidates for removal.
And answering your commentary, you can not make the compiler / refactoring tool decide if any given method is a candidate simply based on the #region its defined in. There is absolutetly nothing that enforces any given method to be defined in any given region, its just visual sugar so refactoring based on regions would be completely unsafe.
Sometimes verbose languages do have advantages, and in this case VB with the implements keyword would make this a compile time error. In C#, you have to use explicitly implemented interfaces which is not a bad option at all. Read here for more details.
Is there any way to do something like this: In Groovy Is there a way to decorate every class to add tracing? but in C#. Since C# doesn't support metaClass I'm stuck as to how to do it. If I could get this solution to work then I would then just iterate through every class using reflection and make it implement the interface.
Thanks,
Joe
Yes, you can use dynamic proxies.
Why don't you take a look at Castle DynamicProxy? http://www.castleproject.org/projects/dynamicproxy/
Or PostSharp, if you want to leverage AOP in a cleaner way:
http://www.sharpcrafters.com/postsharp/documentation
UPDATE
The OP said in some comment:
Ah, I'm actually using PostSharp to output what methods are called and
when. What I'm tring to avoid having to do though is adding an
attribute to every class in my code. So I figured I could just create
an interface like this: [MyAttribute] public interface IDebug {} And
make my classes implement this interface at runtime.
PostSharp supports assembly-level aspects: [assembly:YourAspect]. Later, in your aspect, you can check what method was invoked and to which object belongs to, and do the whole job depending on that.
I have an interface called IStructuredReader that reads some structured data from a file and displays it in a form. It has a member called Sync() that, when implemented, scans the data for a user-specified data pattern.
Some implementations of IStructuredReader don't have sync capability. Those implementations throw NotImplementedException for the Sync() method. I would like to be able to check for this method being implemented, so that I can dim the button on the form if it is not.
I can think of a number of ways that this could be done, all of which seem clumsy and complicated:
Separate the Sync method into its own interface, inherit it for those implementations that support the capability, and attempt to cast the reader object to it to identify the capability,
Write a NotImplementedAttribute, decorate the member with it, and check for the presence of the attribute using Reflection,
Add a HasSyncCapability boolean property to the interface.
Is there a canonical way this is done?
This sounds like you really should have two interfaces. Your Sync() method is obviously adding functionality over your base interface, which suggests that this is really a separate concern, as it's not a requirement of IStructuredReader. I would suggest adding a second interface for the types which support this, which would then be easy to check for in your view layer.
The canonical way is for the interface to expose the methods that will be implemented, so the cleanest solution I see is to create another interface called maybe Syncronizable with just that method. If your object implements that interface you know the method is there, and this is not clumsy at all. Using reflection or the extra attribute are indeed not as clean as solutions, but it doesn't mean you shouldn't go for those if it makes your life easier ;)
I'm adding a new method to a class that implements an interface, and I like to use the "Extract Interface" refactoring and just add the method to the interface. But it doesn't seem like ReSharper supports adding a method signature to an already existing interface.
It feels like I'm missing something, I'm sure it can be done somehow. Maybe I should add the method signature to the interface first, but this is the way I'm working sometimes. Am I missing some shortcut, feature or using ReSharper wrong?
Ctrl+Shift+R to access the refactoring menu then choose Pull Members Up...
You can choose the interface that you want to add the declarations to and also select each method that you want to add to the interface.
Gotta love Resharper! ;-)