流暢的 NHibernate 對映

該 Fluent NHibernate 是一個庫，以幫助你在使用 C#程式碼，而不是 XML 對映的實體對映。流暢的 NHibernate 使用 fluent pattern ，它基於建立對映的約定，它為你提供了可視工作室工具（如 intellisense）的強大功能，以改善你對映實體的方式。

在專案中新增 Nuget 的 Fluent NHibernate 引用，並新增一個 CustomerMap.cs 類：

namespace Project.Mappings
{
    public class CustomerMap : ClassMap<Customer>
    {
        public CustomerMap()
        {
            Table("CUSTOMERS");

            Id(x => x.Id).Column("Customer_Id").GeneratedBy.Native();
            
            //map a property while specifying the max-length as well as setting 
            //it as not nullable. Will result in the backing column having
            //these characteristics, but this will not be enforced in the model!
            Map(x => x.Name)
                .Length(16)
                .Not.Nullable();

            Map(x => x.Sex);

            Map(x => x.Weight);

            Map(x => x.Active);

            //Map a property while specifying the name of the column in the database
            Map(x => x.Birthday, "BIRTHDAY");

            //Maps a many-to-one relationship
            References(x => x.Company);

            //Maps a one-to-many relationship, while also defining which 
            //column to use as key in the foreign table.
            HasMany(x => x.Orders).KeyColumn("CustomerPk");
        }
    }
}

CustomerMap 類來自 ClassMap<T>，它是對映的基類，包含建立 T 實體對映所需的所有方法。Table 方法定義了你要對映的表名。Id 方法用於對映 primery key 列。Map 方法用於對映其他列。