IQueryable & IEnumberable 区别

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Namespace:
System.Collections

    [ComVisibleAttribute(true)]

    [GuidAttribute("496B0ABE-CDEE-11d3-88E8-00902754C43A")]

    public interface IEnumerable

Namespace:
System.Collections.Generic

    public interface IEnumerable
: IEnumerable

Namespace:
System.Linq

    public interface IQueryable
: IEnumerable

    public interface IQueryable
: IEnumerable, IQueryable, IEnumerable

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static void Main(string[]
args)

        {

            //创建数据库访问网关

            using (SchoolDBEntities
schoolEntities = new SchoolDBEntities())

            {

                //查询的结果放入IQueryable接口的集合中

                IQueryable<T_Class>
classesIQue = (from c in schoolEntities.T_Class

                                                   orderby
c.ID

                                                     select
c).Skip<T_Class>(3).Take<T_Class>(3);

                //注意这个AsEnumerable<T_Class>()在分页查询之前，先将其转换成IEnumerable类型

                IEnumerable<T_Class>
classesIEnu = (from c in schoolEntities.T_Class

                                                    orderby
c.ID  

                                                    select
c).AsEnumerable<T_Class>().Skip<T_Class>(3).Take<T_Class>(3);

                //因为启用了延迟加载机制，所以下面调用一下，才会真正去读取数据库

                int i
= 0;

                foreach (var
c in classesIQue)

                {

                    i++;

                }

                Console.WriteLine(i);

                foreach (var
c in classesIEnu)

                {

                    i++;

                }

                Console.WriteLine(i);

            }

            Console.WriteLine("OK");

            Console.ReadKey();

        }