Feature: Create Entities as nullable reference types

[René Larch]

Generate Entity Models with nullable reference type annotations.

Mark nullable columns as nullable reference types.

For Example:

• nvarchar(100) NULL -> string?
• nvarchar(100) NOT NULL -> string

Example Entity:

// 1. switch to nullable annotation context:
#nullable enable

// 2. disable some compiler warnings for non-nullable fields: 
// (instead of doing this it would be possible to initialize non-nullable fields with `.. = null!` )
#pragma warning disable CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider declaring as nullable.

public partial class BlogPost
{
    public BlogPost()
    {
        #region Generated Constructor
        #endregion
    }

    #region Generated Properties
    public int BlogPostId { get; set; }

    public string Title { get; set; }

    public string? Text { get; set; }

    #endregion
}

// 3. restore the warning
#pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider declaring as nullable.


public partial class BlogPostMap : IEntityTypeConfiguration<BlogPost>
{
    public void Configure(Microsoft.EntityFrameworkCore.Metadata.Builders.EntityTypeBuilder<BlogPost> builder)
    {
        #region Generated Configure
        // table
        builder.ToTable("BlogPosts", "dbo");

        // key
        builder.HasKey(t => t.BlogPostId);

        // properties
        builder.Property(t => t.BlogPostId)
            .IsRequired()
            .HasColumnName("BlogPostId")
            .HasColumnType("int")
            .ValueGeneratedOnAdd();

        builder.Property(t => t.Title)
            .IsRequired()
            .HasColumnName("Title")
            .HasColumnType("nvarchar(100)")
            .HasMaxLength(100);

        builder.Property(t => t.Text)
            .HasColumnName("Text")
            .HasColumnType("nvarchar(4000)")
            .HasMaxLength(4000);

        #endregion
    }

    #region Generated Constants
    public struct Table
    {
        public const string Schema = "dbo";
        public const string Name = "BlogPosts";
    }

    public struct Columns
    {
        public const string BlogPostId = "BlogPostId";
        public const string Title = "Title";
        public const string Text = "Text";
    }
    #endregion
}

[Paul Welter]

This work was completed in version 4.5.

add the following to the configuration

project:
  nullable: true