2018-01-10 14:11:30
电商平台 订购和支付 模块
一： 整体示意图
二：构建一个框架来处理 领域模型内部发生的事情--领域事件
- IDomainEvent 标识模型中的 DomainEvent
IDomainEventHandler<T> where T : IDomainEvent 事件处理程序必须实现的接口。
IDomainEventHandlerFactory 用来获取给定领域事件的处理程序的集合
IEnumerableExtension 获取到 IDomainEventHandler 集合之后， 调用它们的处理方法并将领域事件作为动作的实参。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text; namespace Agathas.Storefront.Infrastructure.Domain.Events
{
public static class IEnumerableExtensions
{
public static void ForEach<T>(this IEnumerable<T> source, Action<T> action)
{
foreach (T item in source)
action(item);
}
} }
静态类 DomainEvents -- 为了引发事件。
支持领域事件所需的框架。
二 ： 领域对象
- Payment 值对象， 继承自 Infrastructure -- ValueObjectBase
OrderItem 实体 继承自 EntityBase<int>
与OrderItem 相关联的 Order
EntityBase<int>
using System.Collections.Generic; namespace Agathas.Storefront.Infrastructure.Domain
{
public abstract class EntityBase<TId>
{
private List<BusinessRule> _brokenRules = new List<BusinessRule>(); public TId Id { get; set; } protected abstract void Validate(); public IEnumerable<BusinessRule> GetBrokenRules()
{
_brokenRules.Clear();
Validate();
return _brokenRules;
} protected void AddBrokenRule(BusinessRule businessRule)
{
_brokenRules.Add(businessRule);
} public override bool Equals(object entity)
{
return entity != null
&& entity is EntityBase<TId>
&& this == (EntityBase<TId>)entity;
} public override int GetHashCode()
{
return this.Id.GetHashCode();
} public static bool operator ==(EntityBase<TId> entity1,
EntityBase<TId> entity2)
{
if ((object)entity1 == null && (object)entity2 == null)
{
return true;
} if ((object)entity1 == null || (object)entity2 == null)
{
return false;
} if (entity1.Id.ToString() == entity2.Id.ToString())
{
return true;
} return false;
} public static bool operator !=(EntityBase<TId> entity1,
EntityBase<TId> entity2)
{
return (!(entity1 == entity2));
}
} }
ValueObjectBase
using System.Collections.Generic;
using System.Linq;
using System.Text; namespace Agathas.Storefront.Infrastructure.Domain
{
public abstract class ValueObjectBase
{
private List<BusinessRule> _brokenRules = new List<BusinessRule>(); public ValueObjectBase()
{
} protected abstract void Validate(); public void ThrowExceptionIfInvalid()
{
_brokenRules.Clear();
Validate();
if (_brokenRules.Count() > 0)
{
StringBuilder issues = new StringBuilder();
foreach (BusinessRule businessRule in _brokenRules)
issues.AppendLine(businessRule.Rule); throw new ValueObjectIsInvalidException(issues.ToString());
}
} protected void AddBrokenRule(BusinessRule businessRule)
{
_brokenRules.Add(businessRule);
}
}
}
