I have recently graduated from university with a degree in Computer Science. My degree mainly focused on C#. I want to learn more and get better at what I do. I notice a lot of companies always want their developers to know and use 3rd party tools.
If I was developing C# Windows Forms applications, what 3rd party tools/libraries/controls etc. would be of use to me and for what reason?
I've always liked the Xceed controls. In a lot of cases you could always build your own controls. The biggest advantage to using some of these packages is that it saves you the time and they have also been well tested (if not by the company then by the people that are using them).
I've used a couple of different packages over the years and found that if you can use one it's not that hard to use another. The biggest thing is knowing what is available out there so you don't spend two weeks building something that you could have just paid a few hundred dollars for.
You should know about resharper (helper for VS) Crystal reports - for reports, Some Grid tools (google it, there are many - I wouldn't bother to learn until need one)
and study advanced topics like: WCF, WPF Cruise control or other building tool, bugnet or trac - bug management tools...
And of course - AQtime or other Profiling tools.
You'd probably want to have a look at Silverlight. It's a Microsoft alternative to Flash and uses C#. WPF are also something to look at for interfacing.
It might also be worthwhile looking at MOSS.
The DevExpress and Telerik controls are pretty popular, but not free.
Some 3rd party .Net component providers that I've seen used in companies most often:
They are not free. These kinds of providers offer large libraries of controls that you'd pick from to achieve your specific goals.
The answer to this question depends on how you define "3rd party tools". I usually take that to mean products from companies other than MS but excluding free open source software. When it comes to 3rd party products (for-profit) I cannot think of any common products that I've used or been asked to learn over the last decade that I've been doing .Net development. Most MS shops I've worked with turn to MS solutions (for good or ill depending on your personal view).
That said, in recent years the number and quality of the various FOSS solutions out there has risen dramatically. I use the following whenever I can:
For most of these projects there are many other options, these are just my current favorites. Learn to use these (and WHY they are needed) and you'll be many steps above the average .Net developer (sad but all to true).
Many good suggestions here, I would also add a few other categories of tools:
There are a lot of 3rd party controls that will help you achieve more in less time. But I don't think many of them will really improve your coding skills (calling someone else to do all the work doesn't teach you much about how to actually do thise things yourself, but familiarity with them and the ability to learn new libraries is a good skill to practice)
Resharper is good for improving your coding skills (code analysis), coding style (autoformatting), and it's a great refactoring tool. It's expensive, though.
Microsoft do some free code analysis tools for Visual Studio (FXCop for code analysis, and there is also a Static Analysis addin) which will help improve your code quality.
AtomineerUtils (my own addin) encourages excellence in documentation and generally improves your code quality (by encouraging good naming style, etc)
Focus more on the tools used in the software development process. Enterprise Architect is used for designing applications from a high level. Once you design you application's business classes you can generate your classes' skeletons. You will be responsible for you code implementation once the class structure has been created.
For implementation purposes look at several C# platforms mentioned earlier. You want to focus Microsoft's WPF, WCF, WF. WPF is ok but it can not be used prior to .net 3.0 so check your client's requirements. I'm working on a project that targets the .net 2.0 because of restrictions by the client so the applicaiton was designed in WinForms. Silverlight is an option as well.
In addition, read up on design patterns as this will help you avoid creating high maintenance applications. A good book is Design Patterns in C#.
For testing look at the Visual Studio TFS system or third party programs like NUnit. You can google NUnit. This will help you ensure that your code does what you intended it to do on a granular scale.
Also, take a look at some of the source control software avaialbel like Subversion, Rational ClearCase, Visual SourceSafe. For large projects with multiple developers you'll need a source control tool that has multiple branches so that each developer has his or her own sandbox within the source control system.
I'm a big proponent of ComponentOne and use it in my new applications regularly. I find that if you're proficient in .NET winforms in general, C1 are very easy to pick up on and usually do what you want with little effort.
A couple people mentioned Telerik. I demoed it fairly extensively and found them to be a bit more complicated because they contain a ton of configuration options for look and feel. Awesome if you're some sort of graphic designer, but unless you're building the next Windows Media Player, I think it's overkill. The learning curve for the theming seemed a bit much for what I was trying to accomplish.
C1 and Telerik both run about $1000 to $1300 depending on what license you get.
You should also check out the Krypton toolkit. It free and has a lot of nice controls.