在NHibernate里执行存储过程

NHibernate 是一个基于.Net 的针对关系型数据库的对象持久化类库,来源于非常优秀的基于Java的Hibernate 关系型持久化工具.
在NHibernate里怎么执行存储过程呢?下面有一个简单的例子,使用的MS SQL Server 2000 NorthWind库里的CustOrderHist存储过程.
先建2个实体类:
1.CustOrderHist : Customer Historical Order Summary

    /// <summary>
    /// Customer Historical Order Summary Object Entity Class
    /// </summary>
    public class CustOrderHist
    {
        private string productName;
        private int total;

        /// <summary>
        /// Constructor
        /// </summary>
        /// <param name="productName">Product Name</param>
        /// <param name="total">Total Quantity</param>
        public CustOrderHist ( string productName,int total)
        {
            this.productName = productName;
            this.total = total;
        }

        /// <summary>
        /// Product Name
        /// </summary>
        public string ProductName
        {
            get { return productName; }
        }

        /// <summary>
        /// Total Quantity
        /// </summary>
        public int Total
        {
            get { return total; }
        }

        /// <summary>
        /// Return Product Name And Quantity
        /// </summary>
        /// <returns></returns>
        public override string ToString ( )
        {
            return "Product Name : " + productName + "; Quantity: " + total;
        }
    }

映射关系:

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">
  <sql-query name="GetCustomerOrderHistory">
    <return-scalar column="ProductName" type="String" />
    <return-scalar column="Total" type="int" />
    exec CustOrderHist :CustomerID
  </sql-query>
</hibernate-mapping>

2.Customer:Customer表的2个字段:CustomerID And CompanyName 提供选择CustomerID

/// <summary>
    /// Customer Object Entity Class
    /// </summary>
    public class Customer
    {
        private string customerID;
        private string companyName;

        /// <summary>
        /// Customer ID
        /// </summary>
        public string CustomerID
        {
            get { return customerID; }
            set { customerID = value; }
        }

        /// <summary>
        /// Company Name
        /// </summary>
        public string CompanyName
        {
            get { return companyName; }
            set { companyName = value; }
        }
    }

映射关系:

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">
  <class name="NHibernate.Study.Entity.Customer,Entity" table="Customers">
    <id name="CustomerID">
      <column name="CustomerID" sql-type="string" length="5"/>
      <generator class="assigned" />
    </id>
    <property name="CompanyName">
      <column name="CompanyName" sql-type="string" length="40"/>
    </property>
  </class>
</hibernate-mapping>

再来看看Data Object Access Class:

    public class BllExecPro : IDisposable
    {
        private ISession session = null;

        public void Dispose ( )
        {
            session.Dispose( );
        }

        public BllExecPro ( )
        {
            session = NHLibrary.NHFactory.OpenSession( );
        }

        public IList<Customer> getCustomerIDList ( )
        {
            return session.CreateQuery( "FROM Customer" )
                .SetMaxResults( 10 )
                .List<Customer>( );
        }

        public IList<CustOrderHist> getCustOrderHistList ( string customerID )
        {
            IQuery query = session.GetNamedQuery( "GetCustomerOrderHistory" )
                .SetString( "CustomerID" , customerID )
                .SetResultTransformer(
                    new NHibernate.Transform.AliasToBeanConstructorResultTransformer(
                    typeof( CustOrderHist ).GetConstructors( )[0] ) );
            return query.List<CustOrderHist>( );
        }
    }

页面 HTML:

<form id="form1" runat="server">
    <div>
        <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" DataTextField="CompanyName"
            DataValueField="CustomerID" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged"
            Width="238px">
        </asp:DropDownList>
        <asp:GridView ID="GridView1" runat="server"></asp:GridView>    
    </div>
    </form>

Codebehind:

    protected void Page_Load ( object sender , EventArgs e )
    {
        if ( !IsPostBack )
        {
            bindDropDownList( );
        }
    }

    private void bindDropDownList ( )
    {
        BllExecPro bllExecPro = new BllExecPro( );
        DropDownList1.DataSource = bllExecPro.getCustomerIDList( );
        DropDownList1.DataBind( );
        bindGridView( bllExecPro,DropDownList1.SelectedValue );
    }

    private void bindGridView (BllExecPro bllExecPro, string customerID )
    {
        if ( bllExecPro == null)
            bllExecPro = new BllExecPro( );
        GridView1.DataSource = bllExecPro.getCustOrderHistList( customerID );
        GridView1.DataBind( );
        bllExecPro.Dispose( );
    }

    protected void DropDownList1_SelectedIndexChanged ( object sender , EventArgs e )
    {
        bindGridView(null, DropDownList1.SelectedValue );
    }

浏览页面,通过SQL 事件探察器可以看到在执行 bllExecPro.getCustomerIDList( ) 时实际执行的SQL 语句是：

select top 10 customer0_.CustomerID as CustomerID3_, customer0_.CompanyName as CompanyN2_3_ from Customers customer0_

在执行 bllExecPro.getCustOrderHistList( customerID ) 时实际执行的SQL语句是：

exec sp_executesql N'exec CustOrderHist @p0', N'@p0 nvarchar(5)', @p0 = N'对应的customerID'