.net core EF 关系（二） 私有字段

PropertyAccessMode 枚举 (Microsoft.EntityFrameworkCore) | Microsoft Learn

支持字段 - EF Core | Microsoft Learn

ef 是可以对私有字段配置的

    /// <summary>
    /// 博客
    /// </summary>
    public class Blog
    {
        public Blog()
        {
             Posts = new List<Post>();
        }
        public int Id { get; set; }
        /// <summary>
        /// 导航属性发布集合
        /// </summary>
        public IEnumerable<Post> Posts { get; set; }

        /// <summary>
        /// 私有字段
        /// </summary>
        private string _url;
        /// <summary>
        /// 属性
        /// </summary>
        public string Url =>_url;

        /// <summary>
        /// 私有字段
        /// </summary>
        private string soltCode;

    }
    /// <summary>
    /// 发布
    /// </summary>
    public class Post
    {
        public int Id { get; set; }
        /// <summary>
        /// 外键 博客Id
        /// </summary>
        public int BlogId { get; set; }
        /// <summary>
        /// 导航属性Blog
        /// </summary>
        public Blog? Blog { get; set; }
    }

　　

配置1	builder.Property(x => x.Url).HasField("_url");
配置2 属性对私有字段可读可写	builder.Property(x=>x.Url).HasField("_url").UsePropertyAccessMode(PropertyAccessMode.Field);
配置3 只有私有字段	builder.Property("soltCode").HasColumnName("SoltCode");

 

 public class BlogEntityTypeConfiguration : IEntityTypeConfiguration<Blog>
 {
     public void Configure(EntityTypeBuilder<Blog> builder)
     {
         builder.ToTable("T_Blogs");
         builder.HasKey(x => x.Id);
         //博客和发布时一对多  导航属性 Blog 不为null 外键博客BlogId 必须存在关系 IsRequired() 默认为true
         //builder.HasMany(x=>x.Posts).WithOne(x=>x.Blog).HasForeignKey(x=>x.BlogId).IsRequired();

         //博客和发布时一对多 导航属性 Blog 为null  外键为null 博客BlogId 必须存在关系 IsRequired(false)
         //builder.HasMany(x=>x.Posts).WithOne(x=>x.Blog).HasForeignKey(x=>x.Id).IsRequired(false);

         //博客和发布时一对多 只有导航属性 Blog 没有外键 的必须存在关系IsRequired()
         // builder.HasMany(x => x.Posts).WithOne(x => x.Blog).HasForeignKey("BlogId").IsRequired();

         //博客和发布时一对多 只有导航属性 Blog 没有外键 的必须存在关系IsRequired(false)
         // builder.HasMany(x => x.Posts).WithOne(x => x.Blog).HasForeignKey("BlogId").IsRequired(false);

         //博客和发布时一对多 Blog有导航属性 Post没有有导航属性 Blog 只有有外键 的必须存在关系IsRequired()
         // builder.HasMany(x => x.Posts).WithOne().HasForeignKey(x=>x.BlogId).IsRequired();

         //博客和发布时一对多 Blog没有有导航属性  只有有外键 的必须存在关系IsRequired()
          builder.HasMany<Post>().WithOne().HasForeignKey(x => x.BlogId).IsRequired();

         //私有字段
         //builder.Property(x => x.Url).HasField("_url");

         builder.Property(x=>x.Url).HasField("_url").UsePropertyAccessMode(PropertyAccessMode.Field);

         builder.Property("soltCode").HasColumnName("SoltCode");
     }
 }

　　

迁移文件

 /// <inheritdoc />
 public partial class init1 : Migration
 {
     /// <inheritdoc />
     protected override void Up(MigrationBuilder migrationBuilder)
     {
         migrationBuilder.AlterDatabase()
             .Annotation("MySql:CharSet", "utf8mb4");

         migrationBuilder.CreateTable(
             name: "T_Blogs",
             columns: table => new
             {
                 Id = table.Column<int>(type: "int", nullable: false)
                     .Annotation("MySql:ValueGenerationStrategy", MySqlValueGenerationStrategy.IdentityColumn),
                 Url = table.Column<string>(type: "longtext", nullable: false)
                     .Annotation("MySql:CharSet", "utf8mb4"),
                 SoltCode = table.Column<string>(type: "longtext", nullable: false)
                     .Annotation("MySql:CharSet", "utf8mb4")
             },
             constraints: table =>
             {
                 table.PrimaryKey("PK_T_Blogs", x => x.Id);
             })
             .Annotation("MySql:CharSet", "utf8mb4");

         migrationBuilder.CreateTable(
             name: "Post",
             columns: table => new
             {
                 Id = table.Column<int>(type: "int", nullable: false)
                     .Annotation("MySql:ValueGenerationStrategy", MySqlValueGenerationStrategy.IdentityColumn),
                 BlogId = table.Column<int>(type: "int", nullable: false),
                 BlogId1 = table.Column<int>(type: "int", nullable: true)
             },
             constraints: table =>
             {
                 table.PrimaryKey("PK_Post", x => x.Id);
                 table.ForeignKey(
                     name: "FK_Post_T_Blogs_BlogId",
                     column: x => x.BlogId,
                     principalTable: "T_Blogs",
                     principalColumn: "Id",
                     onDelete: ReferentialAction.Cascade);
                 table.ForeignKey(
                     name: "FK_Post_T_Blogs_BlogId1",
                     column: x => x.BlogId1,
                     principalTable: "T_Blogs",
                     principalColumn: "Id");
             })
             .Annotation("MySql:CharSet", "utf8mb4");

         migrationBuilder.CreateIndex(
             name: "IX_Post_BlogId",
             table: "Post",
             column: "BlogId");

         migrationBuilder.CreateIndex(
             name: "IX_Post_BlogId1",
             table: "Post",
             column: "BlogId1");
     }

     /// <inheritdoc />
     protected override void Down(MigrationBuilder migrationBuilder)
     {
         migrationBuilder.DropTable(
             name: "Post");

         migrationBuilder.DropTable(
             name: "T_Blogs");
     }
 }