小知识点 LINQ中延时求值和主动求值的区别

 1   List<int> list = new List<int>() { 1, 2, 3, 4, 5, 6, 7 };
 2             var temp1 = from c in list where c > 3 select c;
 3             var temp2 = (from c in list where c > 3 select c).ToList<int>();
 4             list.Add(9);
 5             Console.WriteLine("temp1:");
 6             foreach (var item in temp1)
 7             {
 8                 Console.Write(item.ToString() + " ");
 9             }
10             Console.WriteLine("\ntemp2:");
11             foreach (var item in temp2)
12             {
13                 Console.Write(item.ToString() + " ");
14             }