Package and library?

Question

1.00/5 (1 vote)

See more:

A Package and Library are both relevant topics in C# programming.

However, what exactly does a Package contain and what exactly does a Library contain?
Also, what is the difference between a Package and a Library?

What I have tried:

C# Langauge, Programming, Visual Studio 2019

Posted 15-Sep-21 9:36am

CBennigton

Updated 15-Sep-21 16:42pm

v5

Add a Solution

Comments

PIEBALDconsult 15-Sep-21 15:52pm

Neither has specific meaning in C#.

BillWoodruff 16-Sep-21 1:12am

Here we go again ! Don Quixote charges another windmill :)

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

RickZeeland · Accepted Answer · 2021-09-15T09:47:00

Solution 1

A Package is mostly delivered by a Package manager like NuGet, see: NuGet Gallery[^]
A Package can contain anything, e.g. a library.
A library can be a .NET library, see: .NET class library overview | Microsoft Docs[^]
but it can also be a 3rd party library, or you can create your own library, see:
Create a .NET class library using Visual Studio - .NET | Microsoft Docs[^]

Posted 15-Sep-21 9:47am

RickZeeland

Comments

CBennigton 15-Sep-21 16:34pm

After reading the statement you made "A Package is mostly delivered by a Package manager like NuGet", I did more digging on that and I actually came across the following Microsoft documentation https://docs.microsoft.com/en-us/nuget/what-is-nuget which states "Often such code is bundled into "packages" that contain compiled code (as DLLs) along with other content needed in the projects that consume these packages". It also stated "a NuGet package is a single ZIP file with the .nupkg extension"

A Package is a physical thing (being a single ZIP file with the .nupkg extension) and is container for assemblies (dll files). Without your input I probably would not have been able to figure that out. Thank you.

As for what is a Library and what it contains, after inspecting the links you provided it still did not make sense to me. Specifically when looking into the link "Create a .NET class library using Visual Studio"

It gave me the impression that a Library is an "application project" that we create. Then when looking into the code examples it has a namespace and a class called "UtilityLibraries" and "StringLibrary".

So then what exactly is a Library? Is it an application project, a namespace, or a class type?

raddevus 15-Sep-21 17:05pm

Library is probably more conceptual. You may have something like the .NET library which is made up of one or more packages (physical downloadable DLLs).
So a library is a broad term that envelops the conceptual idea of one or more packages that solve a specific problem.
A Graphics Library provides functionality that helps you do drawing in your app (lines, rectangles, etc). And to use that library you download the physical DLLs (aka Assemblies in .NET) which are generally known as packages.
and they are known as packages more now because of NPM (node package manager) and nuget (.NET package manager).

CBennigton 15-Sep-21 20:50pm

"You may have something like the .NET library which is made up of one or more packages (physical downloadable DLLs)." ---> Are you saying that a Library is a container for packages?

raddevus 15-Sep-21 20:58pm

I’m saying it is a concept, an idea, a classification, a model or way of thinking about functionality that is grouped together. That’s it. You can say , “I downloaded a library” but you really downloaded DLLs that contain functionality that has been grouped together. A library is really only conceptual not physical.

CBennigton 15-Sep-21 21:20pm

Oh ok, now I understand what you meant. Thank you correcting me on that :)

However, a "Package" unlike a "Library" does have a physical form correct? Being a single ZIP file with the .nupkg extension and is container for assemblies (dll files)?

The Microsoft documentation https://docs.microsoft.com/en-us/nuget/what-is-nuget states ---> "Often such code is bundled into "packages" that contain compiled code (as DLLs) along with other content needed in the projects that consume these packages". It also stated "a NuGet package is a single ZIP file with the .nupkg extension"

Unless I am totally misinterpretting the above statement made in the MS document.

Richard MacCutchan 16-Sep-21 3:58am

A library has a physical presence also. They are just files, as are packages. In both cases the physical aspect is irrelevant, it is the usage that distinguishes them. But a package could still consist of a single library.

CBennigton 16-Sep-21 8:17am

If the physical presence/form of a package is a a single ZIP file with the .nupkg extension, then what is the physical presence/form of a Library?

I am aware you said knowing that is unimportant but up until now many have said that a package has a physical presence while a library does not.

Richard MacCutchan 16-Sep-21 8:23am

Of course a library has a physical presence. How would your programs use it otherwise? A library contains support classes and methods that can be used by a programmer to make creating applications simpler. A package is just something that can be used to transfer a library (or anything else) between provider and consumer.

The actual file type of a library takes different forms depending on which language is used to create it, and which it supports.

CBennigton 16-Sep-21 8:38am

"Of course a library has a physical presence. How would your programs use it otherwise?" Good point :)

Concerning a "Package" though, it's physical presence is in fact "a single ZIP file with the .nupkg extension" correct?

unless I am misinterpreting the MS documentation.

Richard MacCutchan 16-Sep-21 8:57am

Names and extensions are just a convenience to help us poor humans identify a file type. But they have no actual meaning as far as the file's content is concerned. Think of it this way: a library contains information that an application may make use of: in human terms a book library. A package is something that UPS drops on your doorstep. You need to open it to see the contents.

CBennigton 16-Sep-21 9:16am

Great anology!

By the way I also just came across this document https://docs.microsoft.com/en-us/dotnet/api/system.io.packaging.package?view=net-5.0 which plainly states the physical format of a "package" is a zip file and since packages are distributed via nuget it will have the file extension .nupkg as im sure you already knew. :)

Yet I cannot find anything on libraries?

Richard MacCutchan 16-Sep-21 9:20am

.NET class library overview | Microsoft Docs[^]. But that only applies to .NET. C/C++, Java etc have their own formats.

CBennigton 16-Sep-21 9:32am

"But that only applies to .NET. C/C++, Java etc have their own formats." --> are you saying that document does not apply to C#?

Richard MacCutchan 16-Sep-21 9:33am

No, C# is a .NET language.

CBennigton 16-Sep-21 9:41am

So then that document does apply to C#? Lol

Sorry mate, I don't mean to sound redundant but you worded you initial comment weirdly (and I mean that kindly) that now I feel like i'm misintrepeting every other comment after it.

Richard MacCutchan 16-Sep-21 9:44am

Well, I made the assumption that you understand what the .NET Framework and .NET Core are, and what languages they support.

CBennigton 16-Sep-21 10:07am

Yes, I am aware that C# is a .net language (including C and C++) and how .NET Framework and .NET Core do in fact support the C# language.

Thus, I assume that document does in fact apply to C#?

Richard MacCutchan 16-Sep-21 10:28am

As they say in Ireland when you ask for directions, "ah, you don't want to be starting from here.".

I think these questions are issues that most people would leave until they have got good experience of developing .NET applications. You seem to be starting from a point where you are still missing some basic knowledge. In theory .NET supports any language that can be translated into the Microsoft Intermediate Language, which is somewhere between source and object code. In practice the only languages are C#, VB.NET (Visual Basic) and C++/CLR (a fudged version of C++). Standard C (and C++) are not supported.

And, to be honest, I am still not sure exactly what you are trying to understand or learn.

CBennigton 16-Sep-21 15:49pm

Yes, of course, it made more sense after reading https://microsoft.fandom.com/wiki/Microsoft_.NET_Languages thanks for pointing that out.

Personally I felt I was already at a point were I can ask this these kinds of questions. It seems I have a few knowledge gaps that I have to fill.

Thanks for the assistance. If you decide to create a seperate solution to this post I will also accept it as an answer. If not, it was still much appreciated.

Richard MacCutchan 17-Sep-21 3:45am

Thanks for the feedback. There is no point in creating a solution if you have the information you want.

CBennigton 27-Sep-21 21:46pm

Hey Richard :) much time has passed since the time I made this post.

I have been deeply studying what is a library and a package over the past few weeks.

I now understand what you meant when you said "Of course a library has a physical presence."

I never understood why so many developers kept claiming that a Library does not have a physical presence. When in fact it does.

Accroding to documentation https://docs.microsoft.com/en-us/troubleshoot/windows-client/deployment/dynamic-link-library ---. "A DLL is a library that contains code and data that can be used by more than one program at the same time."

Thus, the physical presence of a Library is a DLL file. While the physical presence of a Package (Nuget Package) is a NUPKG file.

But just as a confirmation, would you agree with what I mentioned above?

In terms of what the physical presence of a Library and a Package is.

It would mean a lot to me if would reply back. Thanks...

Richard MacCutchan 28-Sep-21 3:43am

No. i am afraid you are getting hung up on terminology which does not have a single meaning. A library is not necessarily a DLL, it could be a static library, a jar file or anything else. Similarly a package is
just something that contains other things. A package in Java or Python is nothing like a nuget package. And a package could contain a library (of packages) and vice versa.

The one thing that is constant is that they are all physical objects.

CBennigton 28-Sep-21 13:47pm

So then the physical presence of a Library is NOT a dll file?

Richard MacCutchan 28-Sep-21 13:58pm

No that is not what I said. A library is just a collection of classes and methods that an application calls to perform various functions. It can be a DLL, a LIB, or anything else, but it is still a physical file. But it really does not matter to the application developer. All he or she needs to know is how to link it to the application.

CBennigton 28-Sep-21 14:20pm

oh, wow. So then a Library has many physical forms. As you said could be a ".dll file", an ".lib file", or anything else... I did not know that. Thank you for informing me on that :)

But in C# context it seems like the physical form of a Library will always be a dll file. Would you agree?

After installing packages via nuget and viewing their contents in visual studio, it just shows dll files (aka: assemblies/libraries) and not lib files.