THE NET CORE

ASP NET CORE INTRODUCTION Today knowing how to build a web application is a good skill to have, because the web is the platform on which companies base or evolve their Business. Using ASP.NET Core to build web applications is a good choice because it allows you to build secure applications according to regulations. In this course we will learn this by dropping into a real project, building a real application. WHY ASP NET CORE It is important to stand critically before a new technology. What problems does it solve? Is it suitable for my case? and so on. [...]

THE DOTNET COMMAND The dotnet command provides access to a wide range of functionality. We saw last section the new and run subcommand. Let us look at the most frequently used dotnet commands with a series of slides. Let's look at some commonly used commands. A web application is not an island unto itself; rather, it will connect to third-party services to add functionality to the application itself. To find out if there is a package visit nuget.org, for example, for an electronic invoicing package. [...]

THE PROJECT FILE .CSPROJ Let's analyze the project file. This content is used to instruct the Build platform on how our application should be compiled and published. TargetFramework identifies the version of .NET Core, in our case version eight. The moment version nine comes out we will simply update this value. There is no reference to any source files, i.e., files having the extension .cs as this is not necessary. It will be the Build platform that will take care of searching and compiling all the sources of the project, it is no longer necessary to specify all of [...]

CREATE WEB CONTENT WITH ASP.NET CORE MVC AND RAZOR PAGES As a first step, I leave you the link on azure of the complete project. Some operations have been disabled, however to get an idea about what we will develop is more than enough. This is the link: https://my-course.azurewebsites.net Let's extract a couple of points from the specifications. Two asks us to make a list of courses. If a user finds a course he or she likes, as described in step five, he or she will enter a course detail page with the option to register [...]

ASP.NET CORE MVC LE VIEWS CREATE THE FIRST CONTENT VIEW Razor is the name of the view-engine, which is that component within .NET Core MVC applications that is responsible for processing views to produce HTML. The views are composed of HTML code mixed with C# code, hence the .cshtml extension. Let's look at where views should be created and the subdivision of directories. The name of the View must be the same as that of the Action within the Controller. Let's edit the Controller and display the result. [...]

CURATE UI WITH BOOTSTRAP AND FONTAWESOME To improve the UI what we can do as developers is to get client-side libraries such as Bootstrap and Fontawesome to improve the graphical part of the website. Bootstrap provides a grid of twelve columns. If we take the .col-xl-4 class, its width will be 1/3 of the grid if the user's screen is xl, that is, extra large. Should the browser window shrink, the elements will be organized one below the other. To use Bootstrap you need to download [...]

ORGANIZE THE LOGIC WITHIN THE MODEL In this section we will write Model classes that will allow us to obtain data from a data source that is for the moment still fictitious. The controller acting as the coordinator will go to make use of these classes and pass them to the Views. Let's get into M, that is, the Model in the MVC architecture. Let us first say that there are no patterns that fit every project and every development team, in our project we will use application services that return a ViewModel with the information [...]

EXPLOIT DEPENDENCY INJECTION OF ASP.NET CORE Let's start with a picture that shows us a car engine, look at how many small parts there are. If engineers decided to make so many small components, it is because each one has a different life cycle from the others. Take spark plugs for example, they have a different life cycle than the engine, and the designers decided that through an interface represented by the threading, the spark plug should not be melted into the engine but easily replaced by simply unscrewing the old one and housing the new one. In this [...]

DATA ACCESS WITH ADO.NET CREATE A SQLLITE DATABASE The time has come to use a relational database, and if we use a database it is because we want to persist our application data in a durable way. For this project we will use SQLite which is a very lean, file-based technology that does not require any prerequisites to be installed. We'll use a database-first approach first we'll create the database and tables then we'll go in with the C# code. THE MYCOURSE.DB DATABASE The database should remain private, no one should download it so the best place to place [...]

DATA ACCESS WITH ADO.NET LOADING MULTIPLE RESULT TABLES INTO A DATASET Let us see how it is possible to load multiple DataTables into a DataSet. In this example, two are loaded since there are two queries, But even more can be uploaded. This is the code: The code has been commented on. PROTECT APPLICATION FROM SQL INJECTION When we select a course by requiring that the id be passed to us, that value is actually part of the query string or a form, and the user has the power to modify it. Suppose there is a [...]