CLR Via CSharp----------Delegate&Lambda

CLR Via CSharp----------Delegate&Lambda
 
1. There are some simple samples of how to use the delegate.

 1     class Program

 2     {

 3         static void Main(string[] args)

 4         {

 5 

 6             String[] names = { };

 7 

 8             Counter(1, 3, null);

 9             Counter(1, 4, Conso);

10             Counter(1, 4, Mess);

11 

12             Program p = new Program();

13             Counter(1, 4, new FeedBack(p.Conso2));

14 

15             FeedBack f1 = new FeedBack(Conso);

16             FeedBack f2 = new FeedBack(Mess);

17 

18             FeedBack f = null;

19             f += f1;

20             f += f2;

21             Counter(1, 30, f);

22         }

23 

24         private static void Counter(int from, int to, FeedBack fb)

25         {

26             for (int i = from; i < to; i++)

27                 if (fb != null)

28                     fb(i);

29         }

30 

31         private static void Conso(int value)

32         {

33             Console.WriteLine("Item=" + value.ToString());

34         }

35 

36         private void Conso2(int value)

37         {

38             Console.WriteLine("Item=" + value.ToString());

39         }

40 

41         private static void Mess(int value)

42         {

43             MessageBox.Show("Item=" + value.ToString());

44         }

45 

46         private void Mess2(int value)

47         {

48             MessageBox.Show("Item=" + value.ToString());

49         }

50     }

2. There are much better practices.

1             String[] names = { "Jeff", "Kristin", "Aidan", "Grant", "HaifengCai" };

2             Char charToEnd = 'a';

3             names = Array.FindAll(names, name => name.IndexOf(charToEnd) >= 0);

4             names = Array.ConvertAll(names, name => name.ToUpper());

5             Array.ForEach(names, Console.WriteLine);