I just wondered what other peoples thoughts were regarding related classes in a single or separate .cs file?
If, for example, I have an interface that is implemented by, say an arbitrary 10, other classes, would you place them all in the same file or separate them?
Thanks.
I always go with separate files for each class. It's recommended best practice and it really makes sense.
My approach is that 1 file == 1 class/interface/module/... whatever.
So the filename always reflects what's in there. To me that's the cleanest approach.
I would separate classes into different files. This makes them a lot easier to find in the IDE.
I would place each class in a separate file, and the interface in a separate file as well.
I would give the file the following name .cs
That's a recommended best practice; it allows you to find your classes very fast. I always go with this approach (except when I have inner classes offcourse. :) ).
I must agree with the rest here: 1 class = 1 file.
Also use correct namespacing for full project name as well as folders. Interfaces also go into separate files, but I usually keep enums and structures inside other classes.
Folders can be used to group certain classes together. There is however a small issue when you "run out of names" so to speak.
Example:
Solution: Tedd.CoolApp
Project: Tedd.CoolApp.Engine
Now what do I name the class? I want to name it Engine, but that would give me Tedd.CoolApp.Engine.Engine... :)
The computer could care less about the folder structure you concoct, so this question definitely falls under the category of code readability. As mentioned in this post about standards of code readability, friendly naming, consistency, and logical code separation are fundamental to the creation of readable code.
So, where does that leave us? The creation of files--and the creation of namespaces and file regions--should be consistent. The names should be understandable. And the code in each aggregate category should have something in common, as should be detailed in the category name. Ultimately, with readability, you're considering that your code might be inherited by another poor fellow, and that the naming standards that you've created might help that poor fellow (a "tourist developer", if you will) more easily navigate around in the madness.
That's a lot of talking, so let me get down to brass tacks. These are my rules, but I think they might be helpful to those who are looking to clean up their own code aquariums:
Place one class (or one interface, enum, or struct)
in one file.
The name of the class should be the
name of the file.
Classes that inherit from the same base class should be in the same folder.
If at all possible, a class should be in the same folder as the interface that that class implements.
An interface should have the same name as the class, but should be prefixed with a capitalized "I". It's the only bit of coding advice I still respect from the Hungarians.
The folder name should be a pluralized version of the base class. For example, if we're creating a bunch of Engines, Engine should be the base class name, Engines should be the folder name, and all of the classes that inherit from Engine should be in the Engines folder.
The namespace structure should directly follow the folder structure. So, the namespace for a given set of Engines (example from above) should be placed into a namespace called Engines. If Engines is a subfolder of a subfolder, each subfolder should be its own sub-namespace, e.g. Project1.Subfolder1.Subfolder2.Engines.
When you're dealing with partial classes that need to live in two separate folders (as one piece of the class is autogenerated), place the non-autogenerated class into a folder suffixed with Extensions. In the file, comment out the Extensions namespace like so: namespace FatDish.Engines//.EngineExtensions { ...
When it comes to navigability, the first and second rule are key, as they directly aid in indicating to the "tourist developer" where any given piece of code resides.
That's all I can think of at the moment. It's more important that you're consistent in your conventions than it is that you adopt any particular form of conventionality. That will help other developers understand and consume your code at a quicker rate, and ensure that future developments in the project (written by folks other than yourself) stay within the same conventional, coherent bounds that you've established.
Hope this helps!
Personally I adhere to Single Responsibility Principle where each of my classes has a single behaviour
think of a ecommerce site that has
User Registration
User Login
billing
Supplier Ordering
I would separate these out to a User class, Billing Class and Orders class - the same would then adhere for an interface driven approach - 1 interface for each Responsibility
check out SOLID design principles - each class would then be in owns own file and have a suitable naming convention to help
Related
I'm a beginner programmer, apologies for any stupidity.
Having come from a python background creating small projects with only a few classes, I would have all of my code in one file most of the time.
I've been learning c# recently, and I'm writing a reasonably large console application (10,000 lines +). I obviously can't put everything in one file here, but I'm not sure how I would go about separating the project into smaller segments.
The way I have done this so far, is to create a new project for each namespace within my solution, and split each class into a separate file accordingly. So far, I have around four namespaces. I have written each namespace independently, with a view to use each one going forward in other projects.
I'm at the stage now where I would like to piece together each namespace to build my console application. How do I go about doing this ?
Also, am I structuring my code in the right way ?
Also + 1, is it possible to use files located in a completely different directory within a project ?
Many thanks in advance.
When you start with a namespace, you'll usually use your company or organization name (say, "A"). If you have multiple products/projects and are creating code for that item, you'll want to add a qualifier (say "B", "C", etc., so you'll have A.B, A.C, etc.).
Then general approach is that you want to group types together in a namespace that are related. If you create a type and it is general purpose/utility/one-off solution to a common problem, you'll want to keep it in a broader scoped namespace. When you find you are creating a number of types to support some feature or purpose, you may wish to create a narrow namespace to contain those types. For example, let's say you need to write several data access components for A.B, which contains data transfer objects, data access objects, etc. You may wish, then, to put those types in something like A.B.DataAccess.
However, remember that .NET uses an OOP paradigm. One OOP paradigm is code reuse. So if you access data in both A.B and A.C, you'll do well to create reusable data access components to encourage code reuse in both projects. In that case, you may wish to have a project such as A.Common, which contains common types used by any of your products, that contain general use, generic, or abstract concepts that can be utilized in A.B, A.C, etc.
Let me try and go further with that example.
Project: A.Common (name of assembly)
Purpose: Reusable types for any project
Namespaces: A, A.DataAccess
Types: A.DataAccess.DataAccessObjectBase
Project: A.B (name of assembly)
Purpose: Types for product "B"
References: A.Commmon
Namespaces: A, A.B, A.B.DataAccess
Types: A.B.DataAccess.DataAccessObject (implements A.DataAccess.DataAccessObjectBase)
Project: A.C (name of assembly)
Purpose: Types for product "C"
References: A.Common
Namespaces: A, A.C, A.C.DataAccess
Types: A.C.DataAccess.DataAccessObject (implements A.DataAccess.DataAccessObjectBase)
That's a pretty simplistic and crude example, but hopefully it will help you visualize the relationship between assemblies and namespaces.
Some other tips:
Don't go overboard with creating namespaces, especially when creating deep namespaces (such as A.B.Something.SomeMoreStuff.EvenMoreStuff), unless it sensible. It makes it a little harder for you to find things.
Namespaces should go from broader purpose to narrower purpose. Furthermore, if you create a type in a narrower namespace that relies heavily on stuff from a broader namespace, be sure to place it under the broader namespace. e.g. A.B.Broader.Narrower.
Finally, you should continue to create only one type per source file.
Sounds more or less on the right track. Addressing your questions/structure:
1) Don't need to have each unique namespace be represented by its own project; you can (and likely should) have multiple sub-namespaces within the same project if it helps organize your classes. In your case, it sounds like each one is being programmed as its own stand-alone component, so a project for each one makes sense.
2) Your splitting each class into a separate file is good, keep doing that.
3) Not sure about what you're asking about piecing your code together. Do you mean how to go about physically referencing/linking the projects in Visual Studio or best practices to code/access your API? If the former, you can right-click the "References" item under the project and point to the project (not its compiled DLL). If the latter, there are a variety of programming patterns you can follow, but generally you'll want to abstract a nice API out of the projects so you aren't concerned by the inner-workings of your code.
4) You can definitely reference files from a completely different directory. Just right-click on the project or folder, choose "Add -> Existing Item" then browse to the file. You'll probably want to add it as a "link" so it doesn't physically copy the file: http://msdn.microsoft.com/en-us/library/9f4t9t92%28VS.80%29.aspx
Here's another StackOverflow question that goes a bit into possible solution structures: Solution: Per application, or per application suite
Namespaces help you to organize your code and provide separation of concerns. It could be done also by creating folders or separate projects. With good logic separation you can build maintainable and scalable applications.
When you taking decisions whether to create new folder, or new project you should rely on common sense. For example, creating several projects for hello world application is an overkill. Creating folder for single class is overkill too. But when you have several classes closely related to each other, consider to separate this particular concern from other application. E.g. if you have CustomerRepository, then you add OrderRepository and VendorRepository. Its good decision to highlight concern, which they are represent. Create Repositories folder and move all those classes there.
With large applications its common to separate such concerns as business logic, data access logic, and user interface. Usually classes which relate to these concerns go to separate projects. Keep in mind, that separation done to make your code easier to understand and maintain. So, namespaces should describe concerns to you and to anyone who will maintain your application. E.g. you can use three projects:
FooCompany.BLL
FooCOmpany.DAL
FooCOmpany.UI
Thats acronyms of Business Logic Layer, Data Access Layer and User Interface. There is no 'standard' names. You can use anything which will describe your code better. Here is example of project structure I usually use for company Foo product Bar:
// Assembly for business logic
Foo.Bar.Domain
Foo.Bar.Domain.Model
Foo.Bar.Domain.Services
Foo.Bar.Domain.Repositories
// Assembly for data access
Foo.Bar.Persistence.NHibernate
// Assembly for application services
Foo.Bar.Services
// Project for presentation
Foo.Bar.Presentation.Web
Foo.Bar.Presentation.Web.Controllers
Foo.Bar.Presentation.Web.Views
Btw common practice to start namespace name with name of company you are developing for. SeeNamespace Naming Guidelines. That allows to avoid names conflicts when you have two classes with same name in different namespaces.
I'll begin from last question to first. You can use files located in a completely different directory within a project. I think you go in the right way. About different namespace you can use this code
using System;
using namespace1;
using namespace2;
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Closed 11 years ago.
Possible Duplicate:
How to name C# source files for generic classes
We are currently re-evaluating how we do generic classes when we inherit from a general class. Currently we will put the following two class definitions in the same file
class Foo
{
// code for class
}
class Foo<T> : foo
{
// code for class
}
My question is a simple one, should we keep them in the same file, or split them into separate files?
So far the pros to keeping them in the same file is that you have all the code there right infront of you. The con is that when both classes get sufficiently large, it could become un-readable.
What I would like is good reasons as to why we should do one or the other. If you recommend separate file, I would also like you to include possible naming conventions, or a strategy to get around the fact that we can have only one file named Foo
This is a matter of opinion, but I'd keep them in the same file rather than try to maintain some naming convention for one or the other.
While I subscribe to one class, one file, I think there is value in having these together. We really treat these as one class, right? Typically, Foo will be abstract, and is just a way of using our generic types… well, more generically -- in places where the type parameters don't matter and can't be known at compile time.
If the classes become too large, it should be a red flag anyway that some responsibilities should be broken out.
Unless classes are utterly trivial, I never put more than one in a single file. It's much easier, IMO, to find exactly the class you seek when you have a predictable, unique file name, with namespaces based on folders, generally.
For naming your files, maybe this:
foo.cs
foo_t.cs
foo_tuv.cs // for a foo class with three generics
I'd recommend keeping the classes in the same file. It makes it easier to locate all Foo classes. Also, with code folding (regions) you can easily view only a single class by collapsing the other.
That said, I wouldn't say either way is wrong. In the end this is one of those things that will take some experience to come up with your personal preference and find what works for you in your particular project. And you may find that what works well for one project doesn't necessarily work for your next project.
Answered here:
I think the common solution to this problem is to name the file like
this:
{ClassName}`{NumberOfGenericParameters}
This would give you this filename:
Bag.cs and Bag`1.cs
This is the way Microsoft handle this issue in frameworks like Asp.net
Mvc.
Keep these classes small and you can keep them in one file. If you can't keep them small, divide them. If you prefer keeping them in separate files, it's okay too. But keep them small anyway. In case of separate file, I would use FooGeneric name but someone here How to name C# source files for generic classes recommends Foo`1 (for 1 parameter).
With C++, I can have one class definition in a header file, and have a multiple implementation files by including the header file.
With C#, it seems that there is no such header file, as one class should contain both definition/implementation.
I wonder if the number of lines can be very big, because one can't separate the class into multiple files. Am I correct? I mean, in some cases, one can't change the class design to have smaller classes. In this case, is there a way to solve this problem?
You can separate a class into multiple files using the partial keyword
public partial class ClassNameHere
{
}
It is possible to split the definition of a class or a struct, or an interface over two or more source files using the Partial keyword modifier Link to msdn with the partial class
Partial classes only give you so much. There is still no way, that i know of, to split your class definition from implementation, such that each exists in a separate file. So if you like to develop based on a need-to-know paradigm then you are sort of stuck. Basically there are three levels a developer can work at...
1) Owns all the code and has access to, and maintains all of it.
2) Wishes to use some useful base class(s) which may form part of a framework, or may just be a useful class with some virtual methods, etc, and wishes to extend, or re-implement some virtual base class methods of interest. Now the developer should not need to go and look at the code in the base class(s) in order to understand things at a functional level. If you understand the job of a function, it's input and output parameters, there is no need to go and scratch inside source code. If you think there's a bug, or an optimization is needed, then refer to the developer from 1) who owns and maintains the base code. Of course there's nothing saying that 1) and 2) cannot be associated with the same developer, in which case we have no problem. In fact, this is more than often the case i suspect. Nevertheless, it is still good practice to keep things well separated according to the level at which you are working.
3) A developer needs to use an already packaged / sealed object / component dll, which exposes the relevant interfaces.
Within the context of c#, 1) and 3) have no problems. With 2) i believe there is no way to get round this (unless you change from exposing virtual base methods to exposing interface methods which can be reimplemented in a component owning the would-be base class). If i want to have a look at a class definition to browse over the methods, scaffolding functions, etc, i have to look at a whole lot of source code as well, which just gets in the way of what i am trying to focus on.
Of course if there is class definition documentation external to how we normally do it ( in headers and source files), then i must admit, that within the context of 2), there is not reason to ever look into a class definition file to gain functional knowledge.
So maybe clever Tom's came up with c#, decided to mix class definition with implementation in an attempt to encourage developers to have external documents for their class definitions, and interfaces, which in most IT companies is severely lacking.
Use a partial class as #sparks suggests, or, split into several classes. It's a good rule of thumb that, if you can't fit a class onto a couple of pages, it's complicated enough to need breaking apart.
I am trying to get a handle on the best practice for code
organization within my project. I have looked around on
the internet for good examples and, so far, I have seen
examples of a web project with one or multiple supporting
class libraries that it references or a web project with
sub-folders that follow its namespace conventions.
Assuming there is no right answer, this is what I currently
have for code organization:
MyProjectWeb
This is my web site. I am referencing my class libraries here.
MyProject.DLL
As the base namespace, I am using this DLL for files that
need to be generally consumable. For example, my class "Enums"
that has all the enumerations in my project lives there. As
does class MyProjectException for all exception handling.
MyProject.IO.DLL
This is a grouping of maybe 20 files that handle file upload and
download (so far).
MyProject.Utilities.DLL
ALl my common classes and methods bunched up together in one
generally consumable DLL. Each class follows a "XHelper" convention
such as "SqlHelper, AuthHelper, SerializationHelper, and so on...
MyProject.Web.DLL
I am using this DLL as the main client interface.
Right now, the majority of class files here are:
1) properties (such as School, Location, Account, Posts)
2) authorization stuff ( such as custom membership, custom role,
& custom profile providers)
My question is simply - does this seem logical?
Also, how do I avoid having to cross reference DLLs from one
project library to the next? For example, MyProject.Web.DLL
uses code from MyProject.Utilities.DLL and MyProject.Utilities.DLL
uses code from MyProject.DLL. Is this solved by clicking on properties and selecting "Dependencies"? I tried that but still don't seem to be accessing the namespaces of
the assembly I have selected. Do I have to reference every
assembly I need for each class library?
Responses appreciated and thanks for your patience.
It is logical in that it proceeds logically from your assumptions. The fact that you are asking the question leads me to believe you might not think it is rational.
In general, things should be broken down along conceptual boundaries rather than technical ones. MyProject.IO.DLL is an example of this principle surfacing in your current design. All of the IO things logically go together, so they end up in a single binary. Makes sense.
Breaking things down into namespaces based on their technical type - enum, class, etc. - is going to be a little more problematic.
The dependencies problem is the same one you'd have breaking one class up with many and it is resolved using the same technique: inversion of dependency. Where two things seemingly need to depend on one another, add an intermediary thing that represents the contract between the first two. This can be abstractions, constants, mediators etc... whatever you need to make it so that instead of thing A depending on thing B and thing B depending on thing A, you have things A and B depending on thing C.
In the past I've always gone and called my namespace for a particular project the same as the project (and principle class) e.g.:
namespace KeepAlive
{
public partial class KeepAlive : ServiceBase
{...
Then from other projects whenever i've called that class its always been:
KeepAlive.KeepAlive()...
I'm now beginning to think that this might not be such a good idea, but I'm sort of stumped what to actually call my namespace. What do other people do? Do you just have one namespace for all your projects?
We have this simple scheme:
CompanyName.ProductName
Then the application layer, e.g.
CompanyName.ProductName.Data
CompanyName.ProductName.Web
etc.
And inside divided per module and/or functionality, which normally correspond to folders
CompanyName.ProductName.Web.Shop
CompanyName.ProductName.Web.Newsletter
etc.
BTW: You can find answers to similar questions here:
.NET namespaces
Should the folders in a solution match the namespace?
Having the name of a class being the same as the namespace is a bad idea - it makes it quite tricky to refer to the right thing in some cases, in my opinion.
I usually call the project (and namespace) an appropriate name and then have "EntryPoint" or "Program" for the entry point where appropriate. In your example, I'd probably call the class "KeepAliveService".
CompanyName.ProductName.AreaOfSystem.SubAreaOfSystem
Never call them the same name as a class.
Our areas include things like:
Services
Smartcard
UI
Sub-areas are used sparingly but when relevant:
Smartcard.Mifare
Smartcard.DESFire
Ours don't correspond to folders because logically that may not be the case. To ease solution explorer navigation we might section off certain bits in folders but that doesn't necessarily mean the namespaces should follow the folder structure. Especially if there are only a few files in the folder (a namespace with few types is usually silly).
i name my namespaces with the common descriptor of all the things that go into that namespace.
I like the java package way: com.stackoverflow.Data (or whatwever the primary domain name of your company may be).
That way your namespaces won't be ambiguous.
we stick to the old
uk.co.company.system.layer
scheme that way we keep collisions down to a miniumum as we use a lot of MS Server products and it helps conceptual seperations.
eg.
uk.co.acme.biztalk.bizutils.