paul-csharp-5.event.md

@@ -236,10 +236,37 @@ IEnumerable<IGrouping<char, string>> queryFoodGroups =
     from item in groupingQuery
     group item by item[0];
 
-```
+// 메서드를 이용한 예제
+List<int> numbers1 = new List<int>() { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };
+List<int> numbers2 = new List<int>() { 15, 14, 11, 13, 19, 18, 16, 17, 12, 10 };
+
+// Query #4.
+double average = numbers1.Average();
+
+// Query #5.
+IEnumerable<int> concatenationQuery = numbers1.Concat(numbers2);
+
+// 람다식을 사용한 예제
+// Query #6.
+IEnumerable<int> largeNumbersQuery = numbers2.Where(c => c > 15);
+
+// 메서드와 혼합 사용
 
+// Query #7.
+int numCount1 =
+    (from num in numbers1
+     where num < 3 || num > 7
+     select num).Count();
+
+// 새로운 변수를 사용하는것을 권장
+IEnumerable<int> numbersQuery =
+    from num in numbers1
+    where num < 3 || num > 7
+    select num;
+
+int numCount2 = numbersQuery.Count();
+```
 
-LINQ 
 
 `from` :