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Programming

Execute Raw SQL Scripts in Entity Framework Core

Most of the time, Entity Framework Core will just do the right thing. Every now and then, though, you’ll find that it’s doing something in a bit of a sticky way and you’ll want to take control. Usually it’s when you’re deleting a range on a table with cascading deletes. Here’s an example of the […]

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Programming

Simple Conditional Updates to Entities in ASP.NET Core MVC

When you accept a view model in your .NET Core MVC application, you can request that only certain fields are bound, like this [Bind(“Title”)]. Neat. But when you want to apply the changes to your domain object, you often want to do a similar thing and only update certain fields (and only if they really […]

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Programming

The type or namespace name ‘ApplicationInsights’ does not exist in the namespace ‘Microsoft’

If you uninstall the Application Insights package from a .NET Core MVC project, you might get a few errors as it can’t “remove all the references” that might have made it into your application. The changes to StartUp.cs will be pretty self-explantory, but elsewhere you will get something a bit more off-the-wall as it references […]

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Programming

IISExpress.exe Exited With Access Violation

I was happily typing away at some ASP.NET Core controllers and views, calling a view component to render out some paging links, when this happened… The program iisexpress.exe’ has exited with code -1073741819 (0xc0000005) ‘Access violation’. No exception visible in Visual Studio. No indication of where the error was. Nothing. The Internet supplied links to […]

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Programming

C# 9 Covariant Return Types

Just a quick note on a neat feature in C# 9 that will allow sub-classes to return a covariant return type… what?! Okay, it allows you to return a more specific, or narrower type. For example, we used to have to return the same type… // parent class… public virtual Literature GetLiterature(…) { return new […]

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Programming

C# 9 Non-Null Parameters

This neat C# 9 feature can be summed up in a tiny snippet of code. You know that code analysis warning that tells you that the argument passed might be null… wouldn’t it be nice if you could refuse to accept null? Well, you can. This is the before… public Book(string firstName, string lastName) And […]

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Programming

C# 9 Record Types

Update! Since this article was published, it is almost certain that the keyword for record types will actually be record not data as it was in this early preview. We have taken a quick look at C# 9 Initializers and Immutability and C# 9 Non-Destructive Mutation. Let’s now look at the full transformation from an […]

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Programming

C# 9 Non-Destructive Mutation

There are some phrases in programming that feel like they belong in a superhero movie. Non-destructive mutation is just such as phrase. It refers to a concept in functional programming that means when you want to change the state of an object, you create a copy with the change – rather than changing the original. […]

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Programming

C# 9 Initializers and Immutability

There is currently a compromise in C# that means you can enable object initialization with getters and setters, or you can prevent external code mutating state by hiding the setter… but not both. C# 9 gives us both with the init keyword. Let’s look at before… public class Book { public string Author { get; […]

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Programming

C# 9 Simplified Console Apps

At Microsoft Build 2020, an interesting new “see less boilerplate” feature from C# 9 was demonstrated. It removes all the code to create the class and static Main method, letting you just start typing your code. It makes your code way-less-nested (okay, two levels), but doesn’t miss any of your usual features. For example, args […]