IEnumerable<TSource> Where<TSource>(this IEnumerable<TSource> source, Func<TSource, bool> predicate);

public static IEnumerable<TSource> Take<TSource>(this IEnumerable<TSource> source, int count);

static void Main(string[] args)

{

    List<int> nList = new List<int>();

    IEnumerable<int> sFilter;

    int nCount;

    nList.Add(1);

    nList.Add(2);

    nList.Add(3);

    nList.Add(4);

    nList.Add(5);

    nList.Add(6);

    nList.Add(7);

    nList.Add(8);

    nList.Add(9);

    nList.Add(10);

    nList.Add(11);

    sFilter = nList.Where(f => 

        {  //有多少個元素,這個代碼塊就執(zhí)行多少此.

         if (f > 5)

         {

             if (f.Equals(10))

             {

                 return true;

             }

         }

         else

         {

             return false;

         }

         return false;

         });

    nCount = sFilter.Count();   //這里才開始執(zhí)行Where中的代碼塊.

}

public static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector);

private static IEnumerable<CSLAPropertyInfo> LoadFromType(Type type)

{

    var staticFields = type.GetFields(BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public);

    return staticFields.Where(f => typeof(Csla.Core.IPropertyInfo).IsAssignableFrom(f.FieldType))

        .Select(f =>

        {

            bool isChild = false;

            var property = f.GetValue(null) as Csla.Core.IPropertyInfo;

            //判斷是不是孩子對象

            var fieldType = f.FieldType;

            if (fieldType.IsGenericType && fieldType.GetGenericTypeDefinition() == typeof(PropertyInfo<>))

            {

                var argType = fieldType.GetGenericArguments()[0];

                while (argType.BaseType != null)

                {

                    if (argType.IsGenericType && argType.GetGenericTypeDefinition() == typeof(GBusinessListBase<,>))

                    {

                        isChild = true;

                        break;

                    }

                    argType = argType.BaseType;

                }

            }

            return new CSLAPropertyInfo(property, isChild);

        });

}