Namespaces in C# vs imports in Java and Python

Question

In the Java and Python world, you look at a source file and know where all the imports come from (i.e. you know in which file the imported classes are defined). For example:

Answer 1

How do I know where the Bar-class is declared? Does it come from the namespace foo, or bar, or anothernamespace? Visual Studio allows me to jump there, of course, but what if I am just taking a quick look at a source file in my editor?

Essentially, you don't - but IntelliSense is helping. You cannot actually be sure by just taking a quick glance at the code, but you can hover over the symbol with your cursor, for example. But this is also possible in Python:

from foobar import *
from bazbaz import *

a_bar = Bar()

Where does Bar come from now?

In C#, there does not seem to be such a convention for namespaces, or am I missing something? So, how do I know which directory and file to look in? (after figuring out which namespace the class came from).

No, assemblies do not correspond to directory structures, which, IMHO, is a good thing. The solution explorer is offering a view of all the references added to your project. These references being assemblies, have a concrete representation as a PE file somewhere on your machine. You can easily look at the properties of a reference to see where the physical file is located.

Edit: In order not to contradict other answers in this thread and create confusion: What I mean by saying assembly names do not correspond to directory names is that it is not actually enforced.