Handling Errors and Exceptions in C#. Part 3

This is the third and most comprehensive part about handling errors and exceptions in C#. Here are the first and the second part. Also, you can take a look at the blog post about global exceptions handling in WPF applications.

Errors Handling and many other topics you’ll find in my new video course “API in C#: The Best Practices of Design and Implementation”. Take it with 60% discount! Also, nothing can stop you from reading further)))

The problem of errors handling is really an old one. Despite that, I feel a lack of sources which aggregate the information and reveal all the problems relate to exceptions.
The first question which immediately comes to mind is “Why we need to understand how to properly handle errors?” There are at least two reasons:

  • Do not piss out the users. I know too many applications which fail without even telling the user what went wrong;
  • There is a category of applications which are very errors-sensitive. These are the applications which deal with huge financial

You can open any book on C# and see that for handling (or representing) any unfortunate situations such as validation fails, the critical system fails authors suggest to use exceptions.
The topic is a little bit holy war because there are no silver bullets, but it doesn’t mean that we don’t want to understand the problems which accompany exceptions using.
Several years ago, I asked Uncle Bob about the problems of using exceptions and he replied:

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Abstract Class VS Interface in C#

You can open any C# tutorial and you’ll find some information about abstract classes and interfaces. Most likely, you’ll not find any information about what is the difference between abstract class and interface.
This theme was discussed earlier on the Internet several times but I want to consolidate all the most important thoughts regarding the problem of choosing between an abstract class and interface in this post.
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Designing and Implementing API in C#

Nowadays I’m writing my new programming video course. I chose an interesting topic for the next course: “Designing and Implementing API in C#”.

How to design API? In this course, you’ll learn how to design and implement types in C# so that the other developers won’t hate you when using one of the types developed by you. It means you are going to learn how to write code of the high quality: readable, understandable and reliable.

Improve your knowledge in object-oriented programming in the context of clean coding and building types of high quality.

  • Understand the characteristics of a well designed type
  • Grasp the principles of the convenient API development
  • Write clean code, get rid of unpleasant smells
  • Learn about what exceptions are intended for and how to throw and catch them properly
  • Protect your types from the incorrect usage making them properly encapsulated

And this is far from the full list of topics we will cover in this course.
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MVVM: When EventAggregator (aka MessageBus) is an Anti-Pattern

Very often we can see that developers tend to use static message buses for all kind of interactions between objects. For those, who unaware of this pattern I want to recall that this pattern allows organizing loosely coupled communication channel between objects which don’t want (or can’t) to know each other.
Let’s have a brief look at how a regular example of using this pattern may look like:

public class Sender {
    private readonly IEventAggregator eventAggregator;

    public Sender(IEventAggregator eventAggregator) {
        this.eventAggregator = eventAggregator;
    }

    public void Action() {
        eventAggregator.Publish(new Message());
    }
}

public class Receiver : IHandle<Message> {
    public Receiver(IEventAggregator eventAggregator) {
        eventAggregator.Subscribe(this);
    }
    public void Handle(Message message) {            
    }
}

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C# Static Code Analysis with NDepend

NDepend Icon
Have you heard about the “goto fail” fail? This is a security bug which was introduced by Apple in one of the iOS updates. Long story short, there was a piece of unreachable code which had to perform an important security check of a certificate. But it was unreachable. This is a huge defect in the software of this kind. Any meaningful static analysis tool would find that defect and any meaningful developer would fix such a bug after that. What am I talking about is that the cost of lately caught bugs is much greater than the cost of a bug caught at compile time. I don’t know how the hell Apple slipped up like that, but we are not going to discuss that. We are going to talk about static analysis.

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Learn Enterprise WPF with XAML from Scratch

My first course “Learn Enterprise WPF with XAML from Scratch” went live on Udemy.com and it you can buy it just for 10$! It is a great WPF tutorial for beginners!

In this course, you can learn deeply the concepts and tools that you will need to build fully functional UI-applications with the modern UI-building framework, Windows Presentation Foundation (WPF).

Teaching Approach

No fluff, no ranting, no beating the air. I esteem your time. The course material is succinct, yet comprehensive. All important concepts are covered. Particularly important topics are covered in-depth. For absolute beginners, I offer my help on Skype absolutely free, if requested.

Take this course and you will be satisfied.

Build a strong foundation in WPF with this course

Today, almost all applications have rich UI, console applications are very specific. Learning the essentials of WPF puts a powerful and very useful tool at your fingertips. Being familiar with WPF will make it absolutely easy to move to Universal Windows Platform (UWP) if needed because these technologies rely basically on the same principles and they are both XAML-based.

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Objects Equality in C#. Important Facts That You Should Know

Don’t forget that if you want to get my upcoming video courses with 50% discount, then fill the following  form.

C# provides many ways to compare objects, not only to compare class instances, but also structures. Actually, there are so many ways, that it requires to put them in order. All those possible options of comparing confuse people in case of misunderstanding them and their possible implementations.

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