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nhibernate学习之集合组合依赖

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还是学习compenent的用法，上节实现了简单字段的组合，这节中将讨论两个问题：1.依赖对象有一个指向容器对象的引用。2。集合依赖

作者：ghost 来源：CSDN 2007年9月24日

1.学习目标
   还是学习compenent的用法，上节实现了简单字段的组合，这节中将讨论两个问题：1.依赖对象有一个指向容器对象的引用。2。集合依赖
2.开发环境和必要准备
   开发环境为:windows 2003,Visual studio .Net 2005,Sql server 2005 developer edition
必要准备：学习前六篇nhibernate学习系列Nhibernate学习之起步篇-1 Nhibernate学习起步之many-to-one篇   Nhibernate学习之many-to-many篇 nhibernate学习之三级联(Ternary Associations)篇 Nhibernate学习之性能改善1 nhibernate性能之二级缓存篇

3.通过parent为依赖组合对象映射一个指向容器对象的引用
CompositeUser.cs

public class CompositeUser    {        int _uid;        UserName _name;        public int Uid        {            get            {                return _uid;            }            set            {                _uid = value;            }        }        public UserName Name        {            get            {                return _name;            }            set            {                _name = value;            }        }    }

UserName.cs

public class UserName    {        private string _firstName;        private string _lastName;        CompositeUser _user;        public string FirstName        {            get            {                return _firstName;            }            set            {                _firstName=value;            }        }        public string LastName        {            get            {                return _lastName;            }            set            {                _lastName = value;            }        }        public CompositeUser User        {            get            {                return _user;            }            set            {                _user = value;            }        }    }

映射文件:CompositeUser.hbm.xml

<?xml version="1.0" encoding="utf-8" ?><hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">    <class name="NhibernateSample1.CompositeUser,NhibernateSample1" table="CompositeUser" lazy="false">        <id name="Uid" column="Uid" unsaved-value="0">            <generator class="native" />        </id>        <component name="Name" class="NhibernateSample1.UserName,NhibernateSample1">            <parent name="User"></parent>            <property name="FirstName" column="FirstName"></property>            <property name="LastName" column="LastName"></property>        </component>    </class></hibernate-mapping>

注意parent是指向容器对象的引用
加载一个CompositeUser对象，结果如图

4. 集合组合依赖
Composite.cs

public class CompositeUser    {        int _uid;        UserName _name;        ISet _userNames = new HashedSet();        DateTime _birthDay = DateTime.Now;        public int Uid        {            get            {                return _uid;            }            set            {                _uid = value;            }        }        public ISet UserNames        {            get            {                return _userNames;            }            set            {                _userNames = value;            }        }        public DateTime BirthDay        {            get            {                return _birthDay;            }            set            {                _birthDay = value;            }        }    }

UserName.cs

public class UserName{    private string _firstName;    private string _lastName;    CompositeUser _user;    public string FirstName    {        get        {            return _firstName;        }        set        {            _firstName = value;        }    }    public string LastName    {        get        {            return _lastName;        }        set        {            _lastName = value;        }    }    public CompositeUser User    {        get        {            return _user;        }        set        {            _user = value;        }    }}

映射文件CompositeUser.hbm.xml

<?xml version="1.0" encoding="utf-8" ?><hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">    <class name="NhibernateSample1.CompositeUser,NhibernateSample1" table="CompositeUser" lazy="false">        <id name="Uid" column="Uid" unsaved-value="0">            <generator class="native" />        </id>        <set name="UserNames" table="UserNames" lazy="true">            <key column="Uid"/>            <composite-element  class="NhibernateSample1.UserName,NhibernateSample1">                <property name="FirstName" column="FirstName"></property>                <property name="LastName" column="LastName"></property>            </composite-element >        </set>        <property name="BirthDay" type="DateTime"></property>    </class></hibernate-mapping>