- 增加 ISelect.WhereCascade 实现多表查询时，向每个表中附加条件；

- 增加 Examples 项目 base_entity，利用 BaseEntity 实现简洁的数据库操作；

Examples/base_entity/BaseEntity.cs

@@ -0,0 +1,163 @@
+using FreeSql;
+using FreeSql.DataAnnotations;
+using Newtonsoft.Json;
+using System;
+using System.Diagnostics;
+using System.Linq.Expressions;
+
+[Table(DisableSyncStructure = true)]
+public abstract class BaseEntity
+{
+    private static Lazy<IFreeSql> _ormLazy = new Lazy<IFreeSql>(() =>
+    {
+        var orm = new FreeSqlBuilder()
+            .UseAutoSyncStructure(true)
+            .UseNoneCommandParameter(true)
+            .UseConnectionString(DataType.Sqlite, "data source=test.db;max pool size=5")
+            .Build();
+        orm.Aop.CurdBefore += (s, e) => Trace.WriteLine(e.Sql + "\r\n");
+        return orm;
+    });
+    public static IFreeSql Orm => _ormLazy.Value;
+
+    /// <summary>
+    /// 创建时间
+    /// </summary>
+    public DateTime CreateTime { get; set; }
+    /// <summary>
+    /// 更新时间
+    /// </summary>
+    public DateTime UpdateTime { get; set; }
+    /// <summary>
+    /// 逻辑删除
+    /// </summary>
+    public bool IsDeleted { get; set; }
+}
+
+[Table(DisableSyncStructure = true)]
+public abstract class BaseEntity<TEntity> : BaseEntity where TEntity : class
+{
+    public static ISelect<TEntity> Select => Orm.Select<TEntity>().WhereCascade(a => (a as BaseEntity<TEntity>).IsDeleted == false);
+    public static ISelect<TEntity> Where(Expression<Func<TEntity, bool>> exp) => Select.Where(exp);
+    public static ISelect<TEntity> WhereIf(bool condition, Expression<Func<TEntity, bool>> exp) => Select.WhereIf(condition, exp);
+
+    [JsonIgnore]
+    protected IBaseRepository<TEntity> Repository { get; set; }
+
+    bool UpdateIsDeleted(bool value)
+    {
+        if (this.Repository == null)
+            return Orm.Update<TEntity>(this as TEntity).Set(a => (a as BaseEntity<TEntity>).IsDeleted, this.IsDeleted = value).ExecuteAffrows() == 1;
+        this.IsDeleted = value;
+        return this.Repository.Update(this as TEntity) == 1;
+    }
+    /// <summary>
+    /// 删除数据
+    /// </summary>
+    /// <returns></returns>
+    public virtual bool Delete() => this.UpdateIsDeleted(true);
+    /// <summary>
+    /// 恢复删除的数据
+    /// </summary>
+    /// <returns></returns>
+    public virtual bool Restore() => this.UpdateIsDeleted(false);
+
+    /// <summary>
+    /// 附加实体，在更新数据时，只更新变化的部分
+    /// </summary>
+    public void Attach()
+    {
+        if (this.Repository == null) this.Repository = Orm.GetRepository<TEntity>();
+        this.Repository.Attach(this as TEntity);
+    }
+    /// <summary>
+    /// 更新数据
+    /// </summary>
+    /// <returns></returns>
+    public virtual bool Update()
+    {
+        if (this.Repository == null)
+            return Orm.Update<TEntity>().SetSource(this as TEntity).ExecuteAffrows() == 1;
+        return this.Repository.Update(this as TEntity) == 1;
+    }
+    /// <summary>
+    /// 插入数据
+    /// </summary>
+    public virtual void Insert()
+    {
+        if (this.Repository == null) this.Repository = Orm.GetRepository<TEntity>();
+        this.Repository.Insert(this as TEntity);
+    }
+
+    /// <summary>
+    /// 更新或插入
+    /// </summary>
+    /// <returns></returns>
+    public virtual void Save()
+    {
+        if (this.Repository == null) this.Repository = Orm.GetRepository<TEntity>();
+        this.Repository.InsertOrUpdate(this as TEntity);
+    }
+}
+
+[Table(DisableSyncStructure = true)]
+public abstract class BaseEntity<TEntity, TKey> : BaseEntity<TEntity> where TEntity : class
+{
+    static BaseEntity()
+    {
+        var tkeyType = typeof(TKey)?.NullableTypeOrThis();
+        if (tkeyType == typeof(int) || tkeyType == typeof(long))
+            Orm.CodeFirst.ConfigEntity(typeof(TEntity),
+                t => t.Property("Id").IsIdentity(true));
+    }
+
+    /// <summary>
+    /// 主键
+    /// </summary>
+    public virtual TKey Id { get; set; }
+
+    /// <summary>
+    /// 根据主键值获取数据
+    /// </summary>
+    /// <param name="id"></param>
+    /// <returns></returns>
+    public static TEntity Find(TKey id)
+    {
+        var item = Select.WhereDynamic(id).First();
+        (item as BaseEntity<TEntity>)?.Attach();
+        return item;
+    }
+}
+
+[Table(DisableSyncStructure = true)]
+public abstract class BaseEntity<TEntity, TKey1, TKey2> : BaseEntity<TEntity> where TEntity : class
+{
+
+    /// <summary>
+    /// 主键1
+    /// </summary>
+    [Column(IsPrimary = true)]
+    public virtual TKey1 PkId1 { get; set; }
+    /// <summary>
+    /// 主键2
+    /// </summary>
+    [Column(IsPrimary = true)]
+    public virtual TKey2 PkId2 { get; set; }
+
+    /// <summary>
+    /// 根据主键值获取数据
+    /// </summary>
+    /// <param name="pkid1">主键1</param>
+    /// <param name="pkid2">主键2</param>
+    /// <returns></returns>
+    public static TEntity Find(TKey1 pkid1, TKey1 pkid2)
+    {
+        var item = Select.WhereDynamic(new
+        {
+            PkId1 = pkid1,
+            PkId2 = pkid2
+        }).First();
+        (item as BaseEntity<TEntity>).Attach();
+        return item;
+    }
+}