关于IList、IQueryable、IEnumerable与Func、Expression的关系2-详解

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关于IList、IQueryable、IEnumerable与Func、Expression的关系2-详解

Core Object
NHibernate：ISession -> CreateCriteria
VS.NET：System.Linq -> Queryable、Enumerable

HNibernate工厂类

using System;using System.Collections.Generic;using NHibernate;using NHibernate.Cfg;using System.Configuration;using System.Configuration.Assemblies;using System.Web;namespace TestPro.DAO{    /// <summary>    /// Data access base class    /// </summary>    public class NHibernateHelper    {        protected static ISessionFactory session;        public static ISession GetSession()        {            if (session == null)            {                lock (typeof(NHibernateHelper))                {                    if (session == null)                    {                        //Configuration cfg = new Configuration();                          //cfg.AddAssembly("Domain");                        string cfgpath = System.Web.HttpContext.Current.Server.MapPath("~/" + "hibernate.cfg.xml");//"~/hibernate.cfg.xml");"..\\hibernate.cfg.xml"                        var cfg = new NHibernate.Cfg.Configuration().Configure(cfgpath);//C:\Program Files (x86)\IIS Express(我在这个目录下放了这个文件hibernate.cfg.xml)                                   session = cfg.BuildSessionFactory();                    }                }            }            return session.OpenSession();            //return session.OpenSession(new SQLWatcher());        }    }    public class SQLWatcher : EmptyInterceptor    {        public override NHibernate.SqlCommand.SqlString OnPrepareStatement(NHibernate.SqlCommand.SqlString sql)        {            System.Diagnostics.Debug.WriteLine("sql语句:" + sql);            return base.OnPrepareStatement(sql);        }    }}

NHibernateDAL

using System;using System.Collections.Generic;using System.Linq;using golSysLin=System.Linq;using System.Linq.Expressions;using System.Text;using System.Threading.Tasks;using NHibernate;using Domain;namespace TestPro.DAO{    public class TabUserDAO    {        #region Constructor        /// <summary>        /// Construtor        /// </summary>        public TabUserDAO() : base()        {        }        #endregion        #region Methods        /// <summary>        /// Method responsible to insert TabUser objects into the database        /// </summary>        /// <param name="tabUser"></param>        /// <returns></returns>        public TabUser Insert(TabUser tabUser)        {            ISession session = NHibernateHelper.GetSession();            session.Save(tabUser);            session.Flush();            session.Close();            return session.Get<TabUser>(tabUser.ID);        }        /// <summary>        /// Method responsible to edit TabUser objects from a database        /// </summary>        /// <param name="tabUser"></param>        /// <returns></returns>        public TabUser Edit(TabUser tabUser)        {            ISession session = NHibernateHelper.GetSession();            session.Update(tabUser);            session.Flush();            session.Close();            return session.Get<TabUser>(tabUser.ID);        }        /// <summary>        /// Method responsible to delete TabUser objects from a database        /// </summary>        /// <param name="tabUser"></param>        /// <returns></returns>        public void Delete(TabUser tabUser)        {            ISession session = NHibernateHelper.GetSession();            session.Delete(tabUser);            session.Flush();            session.Close();        }        /// <summary>        /// Method responsible to list TabUser objects from a database        /// </summary>        /// <param name="tabUser"></param>        /// <returns></returns>        public IList<TabUser> List()        {            ISession session = NHibernateHelper.GetSession();            return session.CreateCriteria(typeof(TabUser)).List<TabUser>();//return session.CreateCriteria<TabUser>().List<TabUser>();                         //return session.CreateCriteria(typeof(TabUser)).List<TabUser>().Where(i=>i.ID<10).ToList<TabUser>();        }        public IList<TabUser> List(Func<TabUser, bool> where)        {            return Listable(where).ToList<TabUser>();        }        public IList<TabUser> List(Expression<Func<TabUser, bool>> where)        {            return Listable(where).ToList<TabUser>();        }        /// <summary>        /// Method responsible to list TabUser objects for IQueryable of Func from a database         /// </summary>        public IList<TabUser> ListByQueryable(Func<TabUser, bool> where)        {            return Queryable(where).ToList<TabUser>();        }        /// <summary>        /// Method responsible to list TabUser objects for IQueryable of Expression from a database         /// </summary>        public IList<TabUser> ListByQueryable(Expression<Func<TabUser, bool>> where)            {            return Queryable(where).ToList<TabUser>();        }        public IList<TabUser> ListByEnumerable(Func<TabUser, bool> where)                       {            return Enumerable(where).ToList<TabUser>();        }        public IList<TabUser> ListByEnumerable(Expression<Func<TabUser, bool>> where)        {            return Enumerable(where).ToList<TabUser>();        }        public IQueryable<TabUser> ListOfQueryable(Func<TabUser, bool> where)        {            return Queryable(where);        }        public IQueryable<TabUser> ListOfQueryable(Expression<Func<TabUser, bool>> where)           {            return Queryable(where);        }        public IEnumerable<TabUser> ListOfEnumerable(Func<TabUser, bool> where)                     {            return Enumerable(where);        }        public IEnumerable<TabUser> ListOfEnumerable(Expression<Func<TabUser, bool>> where)        {            return Enumerable(where);        }        //(IEnumerable<TabUser>)//如果性能不行可以把以下函数的返回值都修改为IEnumerable类型，该数据类型是泛型，是安全的。        private IList<TabUser> Listable(Func<TabUser, bool> where)//1 second select        {            //where = (t) => { string name = t.Name.Trim();return t.Name == name;  };            ISession session = NHibernateHelper.GetSession();            return session.CreateCriteria(new TabUser().GetType()).List<TabUser>().Where(where).ToList<TabUser>();//where = t => t.Age > 30 && t.Age < 40;        }        private IList<TabUser> Listable(Expression<Func<TabUser, bool>> where)//3        {            ISession session = NHibernateHelper.GetSession();            return session.CreateCriteria(typeof(TabUser)).List<TabUser>().Where(where.Compile()).ToList<TabUser>();        }        private IQueryable<TabUser> Queryable(Func<TabUser, bool> where)//4        {            ISession session = NHibernateHelper.GetSession();            return global::System.Linq.Queryable.Where(session.CreateCriteria(typeof(TabUser)).List<TabUser>().AsQueryable(), ex => where(ex));        }        private IQueryable<TabUser> Queryable(Expression<Func<TabUser, bool>> where) //2        {            ISession session = NHibernateHelper.GetSession();            return golSysLin::Queryable.Where(session.CreateCriteria(typeof(TabUser)).List<TabUser>().AsQueryable(), where);//        }        private IEnumerable<TabUser> Enumerable(Func<TabUser, bool> where)//1 first select        {            ISession session = NHibernateHelper.GetSession();            return golSysLin::Enumerable.Where(session.CreateCriteria(typeof(TabUser)).List<TabUser>().AsEnumerable<TabUser>(), where);        }        private IEnumerable<TabUser> Enumerable(Expression<Func<TabUser, bool>> where)//3        {            ISession session = NHibernateHelper.GetSession();            return golSysLin::Enumerable.Where(session.CreateCriteria(typeof(TabUser)).List<TabUser>().AsEnumerable<TabUser>(), where.Compile());        }         #endregion        #region Extend        #endregion    }    enum ListOfType    {        IQUERYABLE,        IENUMERABLE    }}

MVC控制器层

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.Mvc;using Business;using Domain;using Ninject;using Ninject.Injection;using Ninject.Modules;using System.Linq.Expressions;using System.Diagnostics;namespace TestMVC.Controllers{    public class TabUserController : Controller    {        TabUserBusiness obj = new TabUserBusiness();        public ActionResult Index()        {            var iterations = 100;            var watch = new Stopwatch();            IList<TabUser> list = new List<TabUser>();            //var list = new List<TabUser>();            watch.Start();            for (int i = 0; i < iterations; i++)            {                Func<TabUser, bool> func = null;                //list = obj.ListByOver();//.ToList();                list = obj.List((Func<TabUser, bool>)(u => 1 == 1)).ToList();            }            watch.Stop();            ViewData["WatchIListFunc"] = watch.ElapsedMilliseconds;            var list2 = new List<TabUser>();            watch.Reset();            watch.Start();            for (int i = 0; i < iterations; i++)            {                list2 = obj.List((Expression<Func<TabUser, bool>>)(u => 1 == 1)).ToList();            }            watch.Stop();            ViewData["WatchIListExpr"] = watch.ElapsedMilliseconds;            var list3 = new List<TabUser>();//.AsQueryable();            watch.Reset();            watch.Start();            for (int i = 0; i < iterations; i++)            {                list3 = obj.ListByQueryable((Func<TabUser, bool>)(u => 1 == 1)).ToList();            }            watch.Stop();            ViewData["WatchIQueryableFunc"] = watch.ElapsedMilliseconds;            var list4 = new List<TabUser>();//.AsQueryable();            watch.Reset();            watch.Start();            for (int i = 0; i < iterations; i++)            {                list4 = obj.ListByQueryable((Expression<Func<TabUser, bool>>)(u => 1 == 1)).ToList();            }            watch.Stop();            ViewData["WatchIQueryableExpr"] = watch.ElapsedMilliseconds;            var list5 = new List<TabUser>();//.AsEnumerable();            watch.Reset();            watch.Start();            for (int i = 0; i < iterations; i++)            {                list5 = obj.ListByEnumerable((Func<TabUser, bool>)(u => 1 == 1)).ToList();            }            watch.Stop();            ViewData["WatchIEnumerableFunc"] = watch.ElapsedMilliseconds;            var list6 = new List<TabUser>();//.AsEnumerable();            watch.Reset();            watch.Start();            for (int i = 0; i < iterations; i++)            {                list6 = obj.ListByEnumerable((Expression<Func<TabUser, bool>>)(u => 1 == 1)).ToList();            }            watch.Stop();            ViewData["WatchIEnumerableExpr"] = watch.ElapsedMilliseconds;            return View(list3);             //http://localhost:55881/TabUser/Index        }    }}

BLL层

using System;using System.Collections.Generic;using System.Linq;using System.Linq.Expressions;using System.Text;using System.Threading.Tasks;using TestPro.DAO;using Domain;namespace Business{    public class TabUserBusiness    {        private TabUserDAO obj;        public TabUserBusiness()        {            obj = new TabUserDAO();        }        public IList<TabUser> List(Func<TabUser, bool> where)//         {            return obj.List(where);        }        public IList<TabUser> List(Expression<Func<TabUser, bool>> where)        {            return obj.List(where);        }        public IList<TabUser> ListByQueryable(Func<TabUser, bool> where)        {            return obj.ListByQueryable(where);        }        public IList<TabUser> ListByQueryable(Expression<Func<TabUser, bool>> where)        {            return obj.ListByQueryable(where);        }        public IList<TabUser> ListByEnumerable(Func<TabUser, bool> where)        {                     return obj.ListByEnumerable(where);        }                public IList<TabUser> ListByEnumerable(Expression<Func<TabUser, bool>> where)        {            return obj.ListByEnumerable(where);        }        public IEnumerable<TabUser> ListOfEnumerable(Func<TabUser, bool> where)        {            return obj.ListOfEnumerable(where);        }        public IEnumerable<TabUser> ListOfEnumerable(Expression<Func<TabUser, bool>> where)        {            return obj.ListOfEnumerable(where);        }    }}

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