Building ASP NET Web API In .NET Core With Entity Framework
An ORM Framework like Entity Framework or EF Core can do all of the above for us and saves a lot of time if we provide the required information to the ORM Framework. The ORM Framework sits between our application code and the Database. It eliminates the need for most custom data-access codes we usually write without an ORM. But Entity Framework can do all of the above automatically for us if we provide the necessary database schema to the Entity Framework. Let us understand this step by step how to achieve the same using Entity Framework. ORM tools increase developer productivity by reducing the redundant task of performing CRUD operations against a database in a .NET Application.
Object-relational mapping (ORM, O/RM, and O/R mapping tool) in computer science is a programming technique for converting data between incompatible type systems using object-oriented programming languages. This creates, in effect, a « virtual object database » that can be used from within the programming language. There are both free and commercial packages available that perform object-relational mapping, although some programmers opt to construct their own ORM tools. If you have an existing database and database tables are already there, you must use the EF Core Database First Approach. In the database-first approach, the EF Core creates the DBContext and Domain Classes based on the existing database schema using EF Core Command.
What Is C# Entity Framework? A Comprehensive Guide
Choose the API option to create a default project with ASP.NET core RESTful HTTP services. Entityframework Core is one Orm that you can use on .net core framework. The .net core is the framework, you can do many things on a framework like develop a web site or another application. In code, you might want to work with objects in an object oriented fashion.
- For a better understanding, please have a look at the following diagram.
- Before .NET 3.5 as a developer, we often used to write ADO.NET code to perform CRUD operations with the underlying database.
- It comes at the cost of another abstraction layer, but it will make the code easier to write.
EF API can map each entity to tables and each property of an entity to a column in the database. I hope this article helps you to understand in a detailed way with step-by-step entity framework meaning pictorial representation and it will be very easy to remember the implementation. Let’s perform DELETE action to remove one of the existing employee records.
Tools and extensions – Entity Framework EF6
As per the above figure, Entity Framework fits between the business entities (domain classes) and the database. This approach first targets a database that does not exist and then creates it. It allows the developers to define and make new models with C# and .NET classes. In this approach, you can use empty databases and add tables too. Prior to .NET 3.5, we (developers) often used to write ADO.NET code or Enterprise Data Access Block to save or retrieve application data from the underlying database.
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of use and privacy policy. Let’s modify the default route in the RouteConfig class so that when the application runs for the first time it will redirect to the Index Action method of Employee Controller. The framework will create the EDMX file within the Models folder.
Entity Framework Code First Approach
EF Core offers new features that won’t be implemented in EF6. However, not all EF6 features are currently implemented in EF Core. Please check the following link for more detailed information.
Open ‘appsettings.json’ and define the connection string. Give the project name and click on Create, proceed with the type of Web Application. Here will see most of the details with pictorial representation and some code snippets. Let me make this article easy to understand and help you explore in a more advanced way. Please put aside 20 minutes to go through this article.
Scalar Property
If this is not clear at this moment how it works, don’t worry we will discuss everything in detail in our upcoming articles. Once the database is ready, in the next step, create a new “Console Application” with the name EFDemo as shown in the below image. Please use the below SQL script to create the database EF_Demo_DB, and tables Departments and Employees, and populate the tables with sample data.
It provides an abstract level to the developers to work with a relational table and columns by using the domain-specific object. It also reduces the code size of the data specific applications and also the readability of the code increases by using it. This is a new technology for accessing the data for Microsoft application. Entity Framework is an open-source ORM framework for .NET applications supported by Microsoft.
Now copy and paste the following code in the main method of the program class as shown below. Here, in this article, I am not going to explain the code. From our next article onwards, I am going to explain everything in detail. Once you click on the Next button, it will open a popup asking you to choose the Entity Framework version as shown below. From this window, select Entity Framework 6.x and click on the Next button as shown in the below image.
Here, in this article, we are going to discuss how to retrieve the data from the SQL Server Database using the Entity Framework Database First Approach in ASP.NET MVC Application. In our upcoming article, we will discuss using business objects as our model. MVC is an architectural pattern to build applications; entity framework is a object relational mapping framework. The Object Services layer includes the Object Context, representing the interaction session between the applications and the data source. The fundamental purpose of the Object Context is to conduct various operations, such as adding and deleting instances of things and querying the database to save the modified state.
Entity Client Data provider
From this window select “EF Designer from database” and click on the Next button as shown in the below image. Here, select the “EF Designer from database” option as we are going to use the Entity Framework Database First Approach. We want to display the data from both tables (Departments and Employees) in a console application as shown below. Pranaya Rout has published more than 3,000 articles in his 11-year career. Then provide a meaningful name for the connection string that is going to save in the web.config file.