NHibernate中的列表vs集合vs包 [英] List vs Set vs Bag in NHibernate

问题描述

NHibernate映射文件中的列表，集合和包之间有什么区别?它们分别与.NET集合有什么关系?

What's the difference between a list, set and bag in the NHibernate mapping file? How does each relate to .NET collections?

推荐答案

NHibernate语义:

NHibernate semantics:

1. 列表:实体的有序集合，允许重复.在代码中使用.NET IList.索引列将需要在NHibernate中进行映射.

1. List: Ordered collection of entities, duplicate allowed. Use a .NET IList in code. The index column will need to be mapped in NHibernate.

设置:唯一实体的无序集合，不允许重复.在代码中使用Iesi.Collection.ISet(v4之前的NH)或System.Collections.Generic.ISet(NH v4 +).覆盖GetHashCode和Equals以指示重复项的业务定义很重要.可以通过定义orderby或通过定义产生SortedSet结果的比较器来进行排序.

Set: Unordered collection of unique entities, duplicates not allowed. Use Iesi.Collection.ISet in code (NH prior to v4) or System.Collections.Generic.ISet (NH v4+). It is important to override GetHashCode and Equals to indicate the business definition of duplicate. Can be sorted by defining an orderby or by defining a comparer resulting in a SortedSet result.

包:实体的无序列表，允许重复.在代码中使用.NET ICollection<T>.列表中的索引列未被NHibernate映射和引用.

Bag: Unordered list of entities, duplicates allowed. Use a .NET ICollection<T> in code. The index column of the list is not mapped and not honored by NHibernate.

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