Exercism aims to provide opportunity for people of all backgrounds by helping them develop their programming skills through practice and mentorship. We provide thousands of exercises spread across over 50 language tracks, and offer both automated and human mentoring.  

1. Packages and Assert
2. Reading and Writing to Files
3. Polymorphism
4. Anonymous Classes
5. Multithreading
6. Introduction to GUI Programming
7. GUI Windows Builder
8. 2-D Game Programming 

dnSpy is a debugger and .NET assembly editor. You can use it to edit and debug assemblies even if you don't have any source code available.

Some Features 

• Debug .NET Framework, .NET Core and Unity game assemblies, no source code required
• Set breakpoints and step into any assembly
• Locals, watch, autos windows 
• All metadata can be edited
• Edit methods and classes in C# or Visual Basic with IntelliSense, no source code required
• Add new methods, classes or members in C# or Visual Basic
• IL editor for low level IL method body editing 

    <div class="container">
        <header class="jumbotron mt-4">
            <div class="display-2 mb-4">Our Mission</div>
            <p class="lead">Wisdom Pet Medicine strives to blend the best in
                traditional and alternative medicine in the diagnosis and
                treatment of companion animals including dogs, cats, birds,
                reptiles, rodents, and fish. We apply the wisdom garnered in
                the centuries old tradition of veterinary medicine, to find the
                safest treatments and cures.</p>
        </header>

    <header class="jumbotron jumbotron-fluid">
        <div class="container">
            <div class="display-2 mb-4">Our Mission</div>
            <p class="lead">Wisdom Pet Medicine strives to blend the best in
                traditional and alternative medicine in the diagnosis and
                treatment of companion animals including dogs, cats, birds,
                reptiles, rodents, and fish. We apply the wisdom garnered in
                the centuries old tradition of veterinary medicine, to find the
                safest treatments and cures.</p>
        </div>
    </header>

<table class="table table-striped table-hover table-bordered table-responsive">
  <thead class="thead-light">

<tr class="bg-danger text-light">

<td class="table-success">$100.00 </td>

        <section class="card mb-5" id="drwinthrop">
            <div class="card-body">
                <img class="card-img img-fluid" src="images/testimonial-mcphersons.jpg"
                    alt="Doctor Winthrop Photo">
                <h2 class="card-title">Dr. Stanley Winthrop</h2>
                <h5 class="card-subtitle">Behaviorist</h5>
                <p class="card-text">Dr. Winthrop is the guardian of Missy, a
                    three-year old Llaso mix, who he adopted at the shelter.
                    Dr. Winthrop is passionate about spay and neuter and pet
                    adoption, and works tireless hours outside the clinic,
                    performing free spay and neuter surgeries for the shelter.</p>
                <a class="card-link" href="#">About Me</a>
                <a class="card-link" href="#">My Pets</a>
                <a class="card-link" href="#">Client Slideshow</a>
            </div>
        </section>

<section class="card mb-5 bg-primary text-light border-warning" id="drchase">

        <section class="card mb-5" id="drsanders">
            <div class="card-header">
                <h2 class="card-title">Dr. Kenneth Sanders</h2>
                <h5 class="card-subtitle">Nutritionist</h5>
            </div>
            <div class="card-body">
                <img class="card-img img-fluid" src="images/testimonial-mcphersons.jpg"
                    alt="Doctor Sanders Photo">
                <p class="card-text">Leroy walked into Dr. Sanders front door
                    when she was moving into a new house. After searching for
                    weeks for Leroy's guardians, she decided to make Leroy a
                    part of her pet family, and now has three cats.</p>
            </div>
            <div class="card-footer">
                <a class="card-link" href="#">About Me</a>
                <a class="card-link" href="#">My Pets</a>
                <a class="card-link" href="#">Client Slideshow</a>
            </div>
        </section>

        <section class="card mb-5" id="drwong">
            <div class="card-body">
                <img class="card-img img-fluid" src="images/testimonial-mcphersons.jpg"
                    alt="Doctor Wong Photo">
                <h2 class="card-title">Dr. Olivia Wong</h2>
                <h5 class="card-subtitle">Preventive Care</h5>
                <p class="card-text">Dr. Wong is a cancer survivor who was
                    fortunate enough to get to spend time with a therapy dog
                    during her recovery. She became passionate about therapy
                    animals, and has started her own foundation to train and
                    provide education to patients in recovery. Now she gets her
                    own dose of daily therapy from her husky, Lilla.</p>
            </div>
            <div class="list-group list-group-flush">
                <a class="list-group-item" href="#">About Me</a>
                <a class="list-group-item" href="#">My Pets</a>
                <a class="list-group-item" href="#">
                    Client Slideshow
                </a>
            </div>
        </section>

    <div class="container">
        <div class="card-group">

<body>
    <div class="container">
        <section class="media mb-5" id="drwinthrop">
            <img class="d-flex align-self-center img-fluid rounded mr-3" style="width:30%"
                src="images/testimonial-mcphersons.jpg" alt="Doctor Winthrop Photo">
            <div class="media-body">
                <h2>Dr. Stanley Winthrop</h2>
                <h5>Behaviorist</h5>
                <p>Dr. Winthrop is the guardian of Missy,
                    a three-year old Llaso mix, who he adopted at the
                    shelter. Dr. Winthrop is passionate about spay and neuter
                    and pet adoption, and works tireless hours outside the
                    clinic, performing free spay and neuter surgeries for the
                    shelter.</p>
        </section>
    </div>
</body>

An easy way to perform background job processing in your .NET and .NET Core applications. No Windows Service or separate process required. CPU and I/O intensive, long-running and short-running jobs are supported. Backed by Redis, SQL Server, SQL Azure and MSMQ. 

PM> Install-Package Hangfire

After installation, update your existing OWIN Startup file with the following lines of code. If you do not have this class in your project or don't know what is it, please read the Quick start guide to learn about how to install Hangfire.

public void Configuration(IAppBuilder app)
{
    GlobalConfiguration.Configuration.UseSqlServerStorage("<connection string or its name>");
    
    app.UseHangfireServer();
    app.UseHangfireDashboard();
}  

You already know how role-based authorization works in ASP.NET Core.

[Authorize(Roles = "Administrator")]
public class AdministrationController : Controller
{
}

But what if you don't want hardcode roles on the Authorize attribute or create roles later and specify in which controller and action it has access without touching source code?

DynamicAuthorization helps you authorize users without hardcoding role(s) on the Authorize attribute with minimum effort. DynamicAuthorization is built at the top of ASP.NET Core Identity and use identity mechanism for managing roles and authorizing users. 

C# for Beginners | Full 2-hour course - YouTube

00:00:00 – Start
00:00:09 – What is C#
00:01:27 – C#: Hello World
00:06:01 – C#: The Basics of Strings
00:14:35 – C#: Searching Strings
00:17:27 – C#: Numbers and Integer Math
00:22:04 – C#: Numbers and Integer Precision
00:27:32 – C#: Numbers and Decimals
00:33:10 – C#: Branches (if)
00:44:29 – C#: “Hello World” Explained
00:50:29 – C#: What are Loops?
00:57:42 – C#: Combining Branches and Loops
01:04:34 – C#: Arrays, List, and Collections
01:15:09 – C#: Sort, Search, and Index Lists
01:22:08 – C#: Lists of Other Types
01:29:51 – C#: Debugging
01:34:30 – C#: Object Oriented Programming – Objects and Classes
01:47:20 – C#: Object Oriented Programming – Methods and Members
01:56:02 – C#: Object Oriented Programming – Methods and Exceptions
02:03:00 – C#: Object Oriented Programming – Catching Exceptions 

The three things I would tell people to learn are economics, writing and C programming, said the Stack Overflow (SO) co-founder and globally-recognised expert on software development

Visual Studio Code, ever growing in popularity and flexibility, has been named by Google as a first-class code editor for working with the company's Flutter SDK and Dart programming language for mobile development.  

It's like JSON. but fast and small.

MessagePack is supported by over 50 programming languages and environments. 

//C#
// Creates serializer.
var serializer = SerializationContext.Default.GetSerializer<T>();

// Pack obj to stream.
serializer.Pack(stream, obj);

// Unpack from stream.
var unpackedObject = serializer.Unpack(stream);