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Namespace Shadowing Class Name

I have the following situation:
A compiled library with the namespace Library which contains class Feauture.
Now there is another library in development, one which intends to utilize the feature, and that has been dubbed Library.Feature. Finally there is a third library: Library.Feature.UI.
When working in the Library.Feature.UI project, which has both other libraries referenced, VS is yelling a lot about trying to using the Feature class, because it is seeing it primarily as a namespace.
I've tried a few different using directives to get around this, as well as trying to qualify the class name, but nothing is working.
Assuming I don't have the ability to change any of the namespaces or existing class names, is there a way to circumvent this issue?

You can either use fully qualified names where you specify the namespace together with the type name or you can use a using directive to create an alias:
using MyFeature = Library.Feature;

You can use alias directives to give a different name to any namespace, and then use that alias to reference that namespace.
By doing this you can differentiate between the class and the namespace.
write the following on top while using namespaces.
using FeatureClass = Library.Feature;
For more knowledge on this, you can refer:
https://msdn.microsoft.com/en-us/library/aa664765%28v=vs.71%29.aspx
Let me know if you have any further issue...

This should do the trick (references)
using FeatureClass = Library.Feature;

C# Using Directive - Including All Child Libraries [duplicate]

Sorry if this question was asked already.
I started studying C# and noticed that C# doesn't automatically import nested namespaces.
I don't understand:
using System;
should automatically import all classes contained in the System namespace right?
So there should be no need for me to write
using System.Windows.Form;
I would understand if using Windows.Form even worked. But the compiler could not resolve it! What is the point of the using System; before it then?
So why does using System; not import System.Windows automatically as well as System.Windows.Forms - sorry if the word import is wrong here.. maybe move to global namespace is the right terminology.

C# is not Java.
A using directive is used so you don't have to type in the fully qualified name of a type. It also helps with disambiguating type names (using aliases for instance).
In the case of Console, for example, you don't need to type System.Console.
It is important to understand the difference between a namespace and an assembly - a namespace is a logical grouping of types. An assembly is a physical grouping of types. Namespaces can span assemblies.
When you reference an assembly (this is more like importing a package in Java), you gain access to all of the public types in it. In order to use a type you need to uniquely identify it. This is done through the namespace - the using directive simply means you don't have to type the fully qualified name of the type.

The using directive has two uses:
To allow the use of types in a namespace so that you do not have to
qualify the use of a type in that namespace:
using System.Text;
To create an alias for a namespace or a type. This
is called a using alias directive.
using Project = PC.MyCompany.Project;
http://msdn.microsoft.com/en-us/library/sf0df423.aspx
However, you have to note that System and System.Windows.Form are not connected through name itself in anyway. If you import (using) System that means you will use the System assembly types in this class. Actual reference you specify in references section in Visual Studio project which you can really use (even without using statement, as this is just a shortcut for types).

C# doesn't import nested namespaces and this is by design.
Namespace scope lets you organize code and gives you a way to create
globally unique types.
Nested namespaces are used to group related functionality, but use parts of it on-demand.
I guess you wouldn't want to have all the types from such a big namespace like System if the only thing you need is System.Windows.
So probably the question is why C# doesn't have something like using System.*; like java does. I don't know the answer, but I guess this is because of KISS principle. It's something like using
select *
you will never know what types you will add and how they will affect existing code.

Even in Java you'd have to explicitly write
import System.*;
Much of the time you don't want all of the nested namespaces. These would simply clutter IntelliSense.

The "using" syntax allows you shorthand access to namespaces that are already listed as References in the project settings. If the namespace is listed as a reference you already have access to it by it's full name without the "using" directive. Just saves keystrokes.

"Using" a given namespace means that you will get access to all definitions implemented directly in it, not that it will recursively look up the embedded namespaces; doing otherwise would defeat the purpose of the "Using" statement.
Namespaces exist to avoid class name ambiguity. The "Using" statement is here to avoid the use of fully qualified types nested in namespaces, when you know no (or little) ambiguity may occur.

No, this is not how it works.
And I will give a good argument against what you said: intellisnse would go crazy and finding the what you want would be hell.
You do have access to everything on every namespace available (with dots), the using keyword simplifies this because you don't have to specify from which namespace a class or struct is "coming from" (I mean, defined).

Including namespaces in C# [duplicate]

This question already has answers here:
Using Statements vs Namespace path? C#
(6 answers)
Closed 8 years ago.
I want to use Console.WriteLine method. There are two ways
using System; and then Console.WriteLine(); this is one way
System.Console.WriteLine(). this is another way
What is the difference between these two?
Will all the classes include under system namespace if i use using System; ?
Will console class only include when i use System.Console.WriteLine statement?

using System is just a syntactic sugar that allows you to access all the classes under the namespace without specifying the namespace. So yes, using System imports all the classes that are defined in System namespace then you can access them by their name.
In case where you include two namespaces that has two identical class then you will have to use fully-qualified name of the class to avoid ambiguity.
Also it is worth noting that this is just a shortcut. The using directive doesn't add anything to your project.So if you need to use a class or a function from a third-party dll, first you have to add a reference to your assembly (*.dll file) then you can use using directive.

using System;
<CODEHERE>
<CODEHERE>
Console.WriteLine("Text");
<CODEHERE>
<CODEHERE>
This is the more generic, and usual way of doing it for two reasons:
It is more readable
And if you wanted to use another class of System, you would already have the import.
Using the other method:
System.Console.WriteLine("Text");
is a lot more rare to see, and you would have to write out the fully qualified name of any other System class, or just to use it again:
System.Console.WriteLine("Text");
System.Console.WriteLine("Text2");
If you look back at what the using statement actualy means:
'Using' is a statement used to stop the programmer from repeatedly having to type the fully qualified namespace for everything.
I would use the 'using System' version.

System.Linq.Queryable is not an attribute class error?

I am getting an error when adding [Queryable] the error is similar like this 'System.Linq.Queryable' is not an attribute class
when I tried to add namespace before [System.Web.Http.Queryable] I got another error
The type System.Web.Http.QueryableAttribute exists in both
System.Web.Http.OData.dll and System.Web.Http.dll
How to resolve this?

As Soner Gönül said.
Most probably you have
two using directives in your cs file:
using System.Web;
using System.Web.Http;
both define the attribute. Either remove one of those namespaces or fully qualify your attribute either as
[System.Web.Queryable]
// or
[System.Web.Http.Queryable]
Depending what the difference is of both and what you need. You will find more help in the corresponding MSDN documentation of both.

You have two DLL references that contain exactly the same namespace, containing a class with exactly the same name. The simplest solution is to remove one of these references from your project. If you need them both for some other reasons then the only solution I can think of is to create another project which will wrap the classes you need within other classes in a different namespace.

C# using statement at the top of the code page

Almost all C# files have using statements at the top of the page
i.e.
using System;
using System.IO;
//code....
What do the using statements mean that are at the top of the page? Why is the syntax different from other using statement declarations.
i.e.
using (ResourceType resource = expression) statement

Those are using directives. They tell the compiler which namespaces to look in to find the classes you use in your code.
They look different (and are completely different) from the using statement which defines a scope for disposable objects.

These statements tellt he compiler which namespaces to look in to find the classes you are using in the code.
For example if you have
using System.IO;
Then your code to read all text of a file can be
File.ReadAllText("MyFile.txt");
rather than
System.IO.File.ReadAllText("MyFile.txt");

The using directive (as opposed to the using statement you mention that handles disposable objects) allow you to not specify the whole namespace of a class
i.e. if there is a class called
System.IO.FileStream
Then you could put
using System.IO;
And refer to it as
FileStream
(as long as the compiler can only determine a single thing that might mean)

using is a contextual keyword; it has more than one meaning, depending on how it's used.
At the head of a .cs file, it works like the java import instruction, specifying namespaces to search when looking for a type. If it's not listed, you must fully qualify types you use, which gets cumbersome. However, importing namespaes you don't need is wasteful and can introduce ambiguities.

Check out http://msdn.microsoft.com/en-ca/library/zhdeatwt(v=VS.80).aspx
The using keyword has two major uses:
As a directive, when it is used to
create an alias for a namespace or to
import types defined in other
namespaces. See using Directive.
As a statement, when it defines a
scope at the end of which an object
will be disposed. See using Statement.

1) The using keyword followed by a resource path provides a reference to a library in order to use additional/special classes and methods. This is similar to import-like keywords in other languages.
2) The using statement obtains the resource specified, executes the statements and disposes the object (releases from memory).

The kind of usings that exists are the
using directive, the one on top of files. It has two versions
using System.Text; - search this namespace for types that are not given by a fully qualified name. Similar to the %PATH% system variable.
using Project = PC.MyCompany.Project; - an "alias" for a type or namespace
The other kind of using is the using statement, the one with using (var foo = IDisposable){...}
This is a shortcut for a try-catch-block that calls Dispose on the foo-variable at the end.