LindDotNetCore~ISoftDelete软删除接口
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2022-07-07 12:10:54
回到目录 概念 ISoftDelete即软删除,数据在进行delete后不会从数据库清除,而只是标记一个状态,在业务范围里都不能获取到这个数据,这在ORM框架里还是比较容易实现的,对传统的ado来说需要对sql统一进行拦截和条件过滤. 实施步骤 代码实现 1 实体继承ISoftDelete 2 数据 ......
概念
ISoftDelete即软删除,数据在进行delete后不会从数据库清除,而只是标记一个状态,在业务范围里都不能获取到这个数据,这在ORM框架里还是比较容易实现的,对传统的ado来说需要对sql统一进行拦截和条件过滤.
实施步骤
- 实体继承ISoftDelete
- 数据上下文实现对IsDeleted的过滤
- 对删除方法进行调整,添加对ISoftDelete的支持
代码实现
1 实体继承ISoftDelete
protected override void OnModelCreating(ModelBuilder modelBuilder) { foreach (var entityType in modelBuilder.Model.GetEntityTypes()) { // 1. Add the IsDeleted property entityType.GetOrAddProperty("IsDeleted", typeof(bool)); // 2. Create the query filter var parameter = Expression.Parameter(entityType.ClrType); // 3. EF.Property<bool>(post, "IsDeleted") var propertyMethodInfo = typeof(EF).GetMethod("Property").MakeGenericMethod(typeof(bool)); var isDeletedProperty = Expression.Call(propertyMethodInfo, parameter, Expression.Constant("IsDeleted")); // 4. EF.Property<bool>(post, "IsDeleted") == false BinaryExpression compareExpression = Expression.MakeBinary(ExpressionType.Equal, isDeletedProperty, Expression.Constant(false)); // 5. post => EF.Property<bool>(post, "IsDeleted") == false var lambda = Expression.Lambda(compareExpression, parameter); modelBuilder.Entity(entityType.ClrType).HasQueryFilter(lambda);
2 数据上下文实现对IsDeleted的过滤
public class ProductInfo : EntityBase, ISoftDelete { public string Title { get; set; } public decimal Amount { get; set; } public int Discount { get; set; } public int Inventory { get; set; } public DateTime DeletedDate { get; set; } public string DeletedUser { get; set; } public bool IsDeleted { get; set; } /// <summary> /// domain method /// </summary> /// <returns></returns> public decimal GetSaleAmount() { return Amount * Discount / 100; } }
3 对删除方法进行调整,添加对ISoftDelete的支持
代码来自Lind.DotNetCore.Repository.EFRepository类型
public void Delete(TEntity item) { if (item != null) { if (typeof(ISoftDelete).IsAssignableFrom(item.GetType())) { Db.Entry(item).State = EntityState.Modified; var delEntity = item as ISoftDelete; delEntity.DeletedDate = DateTime.Now; delEntity.IsDeleted = true; } else { //物理删除 Db.Set<TEntity>().Attach(item as TEntity); Db.Entry(item).State = EntityState.Deleted; Db.Set<TEntity>().Remove(item as TEntity); } this.SaveChanges(); } }
上面几行代码实现了对软删除的完整支持,从ISoftDelete接口到数据上下文里的过滤IsDeleted,再到优化后的Delete()方法,一切看上去都很优雅!
对于软删除支持的框架也很多,像abp,eshopconationer,linddotnetcore等!
欢迎大家的阅读与思考!