is it a good idea to have classes with the same name in different namespace in c#?

Question

for example, we have two classes for parsing the resumes, one to parse Excel and the other to parse HTML.what my colleagues love to do is to name these two classes the same name and put them into different namespace,like shown as below:

namespace XX.ResumeParsers.Excel
class ResumeParser{}

namespace XX.ResumeParsers.Html
class ResumeParser{}

I feel it is not a good idea, I'll prefer to rename the classes, and put them into one namespace(but in different files if needed):

//in Excel folder under ResumeParsers folder
namespace XX.ResumeParsers
class ExcelResumeParser{}

//in Html folder under ResumeParsers folder
namespace XX.ResumeParsers
class HtmlResumeParser{}

thus, the Hierarchy still exists in the folder, but the namespace is the same(do not match the folder hierarchy exactly), is that OK?

and if I am right, any idea how to persuade my colleagues? or is there any significant drawback in their solution?

thanks.

Answer 1

If parsers have one base interface and some specific helper classes, but used only over base interface, first solution (different namespaces) is best. Because:

• Can be divided on different assemblies
• Each parser independent from other

Answer 2

It's not usually a good idea, no - particularly if you need to use both classes from the same code. Whether they should be in different namespaces or not is a separate decision, but I'd definitely call them HtmlResumeParser and ExcelResumeParser instead of trying to make the namespace communicate context. It will make it much easier to determine exactly what you're talking about when reading code.

Answer 3

There isn't any absolute right or wrong here, but putting similar classes in the same namespace seems like a good idea.

You can look at the StreamReader and StringReader as a similar example in the framework. They both imlplement the same interface (TextReader), and are both in the System.IO namespace, eventhough the StringReader class isn't doing any actual I/O as it reads from a string in memory.

Regardless of whether you put the classes in the same namespace or not, you should try to make the class names unique. If you ever need both classes in the same file, it's a hassle to have to specify the full namespace all the time.

Answer 4

I can tell from experience - worked on a large codebase involving a similar example - that the second option is much better in terms of readability. In my case, I would love to get a hold of the programmer that chose to do it the other way around :).

In general, for people writing the code, it's always clear which class is being used and why - but think about people reading it - will they be able to tell at a glance which parser is used in your code?

There's also the case when you need both classes in the same method - Jon already mentioned it - you'll get conflicts then and will need to use the full namespace - which is a pain. And even if you know you don't - somebody else in the future might need to. And will probably want to get a hold of you, too :).

Answer 5

I'd say it's probably OK if any given code will use either one or the other but not both, and if the two are implemented in separate assemblies. If they're in the same assembly, or if one class will want to use both, then I'd prefer distinct class names.