相关疑难解决方法(0)

我有以下实体：

public class Level
{
    public int LevelId { get; set; }
    public int? ParentLevelId { get; set; }
    public string Name { get; set; }

    public virtual Level Parent { get; set; }
    public virtual HashSet<Level> Children { get; set; }   
}

我在这里遇到麻烦的是Children属性，它在Fluent API中是这样配置的：

modelBuilder.Entity<Level>()
    .HasOne(x => x.Parent)
    .WithMany(x => x.Children)
    .HasForeignKey(x => x.ParentLevelId);

这导致迁移添加了一些其他列：

migrationBuilder.AddColumn<int>(
    name: "LevelId1",
    table: "Level",
    nullable: true);

migrationBuilder.CreateIndex(
    name: "IX_Level_LevelId1",
    table: "Level",
    column: "LevelId1");

migrationBuilder.AddForeignKey(
    name: "FK_Level_Level_LevelId1",
    table: "Level",
    column: "LevelId1",
    principalTable: …

根据我的模型，我想一次将数据提取为树列表。

public class FolderInResearch : EntityBase
{
    public FolderInResearch()
    {
        SubFolders = new List<FolderInResearch>();
    }
    public string Name { get; set; }      
    public Guid? ParentFolderId { get; set; }
    [ForeignKey("ParentFolderId")]
    public ICollection<FolderInResearch> SubFolders { get; set; }        
}