Custom Conventions - (EF Advanced Topics)

Entity Framework is a popular ORM framework that makes it easy to work with databases in .NET applications. In addition to its built-in conventions, Entity Framework allows you to create your own custom conventions to further customize your data model. In this tutorial, we'll discuss custom conventions in Entity Framework and how to use them.

Syntax

There is no specific syntax for creating custom conventions in Entity Framework as it can be done in many different ways depending on the scenario.

Example

Let's look at an example of how to create a custom convention in Entity Framework. Suppose we have the following model:

public class MyEntity
{
    public int Id { get; set; }
    public string Name { get; set; }
    public int? Order { get; set; }
}

We want all our string properties that end with "_code" to be indexed in the database. We can create a custom convention to automatically add the index for all string properties that end with "_code" as shown below:

public class StringPropertyCodeConvention : Convention
{
    public StringPropertyCodeConvention()
    {
        Properties<string>()
            .Where(p => p.Name.EndsWith("_code"))
            .Configure(p => p.HasIndex());
    }
}

In this example, we are creating a custom convention that checks for string properties that end with "_code" and adds an index to them. We are then applying this convention on our context:

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    base.OnModelCreating(modelBuilder);

    modelBuilder.Conventions.Add(new StringPropertyCodeConvention());
}

Now all string properties that end with "_code" in our model will automatically have an index added to them.

Explanation

Custom conventions in Entity Framework allow you to further customize your data model beyond the built-in conventions. You can create your own conventions to automatically add indexes, set default values, or perform other customizations that are not provided by Entity Framework out of the box.

Use

Custom conventions are useful when you want to apply a certain behavior across all or some entity types in your model. They can help you avoid writing the same code over and over again, reducing boilerplate code and saving time.

Important Points

Here are some important points to keep in mind when using custom conventions in Entity Framework:

• Custom conventions can help you further customize your data model beyond the built-in conventions.
• Custom conventions apply to all or some entity types in your model, reducing boilerplate code and saving time.
• Custom conventions can help enforce coding standards, promote consistency, or optimize database performance.

Summary

In this tutorial, we discussed custom conventions in Entity Framework and how to create and apply them. We covered the syntax, example, explanation, use, and important points of using custom conventions in Entity Framework. By understanding custom conventions, you can further customize your data model and improve your development experience in Entity Framework.