C#中的let字句应用示例

using System;using System.Linq;namespace UseLet{ class Program { static void Main() {  string[] strings = {  "A penny saved is a penny earned.",  "The early bird catches the worm.",  "The pen is mightier than the sword."  };  var earlyBirdQuery = from sentence in strings     let words = sentence.Split(' ')     from word in words     let w = word.ToLower()     where w[0] == 'a' || w[0] == 'e' || w[0] == 'i' || w[0] == 'o' || w[0] == 'u'     select word;  foreach (var v in earlyBirdQuery)  {  Console.WriteLine("/"{0}/" starts with a vowel", v);  }  Console.WriteLine("Press any key to exit");  Console.ReadLine(); } }}