Stateful components in React

I haven’t dove into state in functional components yet. But I am learning about state in class components.

When building a class in React, it’s helpful to extend (in C# we call this an override (inheritance)) React.Component. In order to pass arguments (props) to this class though, you must pass the props into the class constructor as well as into the parent (React.Component). That’s accomplished by using the super keyword.

The nice thing about state in a React class, is that it’s asynchronous out of the box. We can set off a task in the constructor and when you have a callback function that’s tied to this.setState, React will automatically recall the render method and update the state of that component. See my example below:

Basic react state

 

How To Start with src and tests Folders in your Solution File in Visual Studio 2019

Organizing your code into src and tests folders on GitHub seems to be getting more and more popular. However, in Visual Studio 2019, it’s not very easy to accomplish. Here is how I do it.

Firstly, let me show you the final outcome:

To get there requires some Command line. First open a Command window and change to your local root folder for your application. In my case it’s C:\Code\NameOfCoolApp.

Once in the root folder of your application, type this in:

dotnet new sln

You should get something similar to The template “Solution File” was created successfully.

Next, we’re going to stub out one of your projects in the solution, so use whatever your naming convention is here. In my case, we’re going to stub out the Domain project. So from that same command window, type:

dotnet new classlib -o src/NameOfCoolApp.Domain

You should then see something like The template “Class Library” was created successfully and ending with Restore succeeded.

Next, I add a stubbed Unit Test:

dotnet new mstest -o tests/Domain.UnitTests

Following the successful message, we’re then going to add the above two items to the Solution by starting with:

dotnet sln add src/NameOfCoolApp.Domain

And finally:

dotnet sln add tests/Domain.UnitTests

From here you should be able to open the Solution file with VS2019 and be good to move on with the rest of your project within Visual Studio.

 

.NET Core 3.1 Missing From Target framework in VS2019 [FIXED]

I cloned a repository that was targeting .NET Core 3.1. Trying to run it in VS 2019 ended with this error:

The current .NET SDK does not support targeting .NET Core 2.1. Either target .NET Core 2.0 or lower, or use a version of the .NET SDK that supports .NET Core 2.1.

I looked at the properties of the project and I couldn’t see anything higher than .NET Core 2.2 in my Target frameworks list.

I spent more hours that I care to admit to here. I checked that .NET Core 3.1 both x64 and x32 were installed. They were.

I checked that C:\Program Files\dotnet was in my Path. It was.

It turned out that I had a global.json file in my root C:\Code folder, where I have all my local code projects, that was limiting my targeting of any child folders to 2.2.

I removed that global.json file and viola! I can now see .NET Core 3.1.

 

RadControls ComboBox

When doing any kind of validation on your aspx pages, you must go back and set the CausesValidation property of most of your controls to “false”.  My RadComboBox wasn’t firing any postbacks until I did that.  I also had to set the same property on all my RadTabStrips because by default, they want to validate when you click on other tabs.