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

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

 

1. There are some simple samples of how to use the delegate。

    class Program
    {
        static void Main(string[] args)
        {

            String[] names = { };

            Counter(1, 3, null);
            Counter(1, 4, Conso);
            Counter(1, 4, Mess);

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

            FeedBack f1 = new FeedBack(Conso);
            FeedBack f2 = new FeedBack(Mess);

            FeedBack f = null;
            f += f1;
            f += f2;
            Counter(1, 30, f);
        }

        private static void Counter(int from, int to, FeedBack fb)
        {
            for (int i = from; i < to; i++)
                if (fb != null)
                    fb(i);
        }

        private static void Conso(int value)
        {
            Console.WriteLine("Item=" + value.ToString());
        }

        private void Conso2(int value)
        {
            Console.WriteLine("Item=" + value.ToString());
        }

        private static void Mess(int value)
        {
            MessageBox.Show("Item=" + value.ToString());
        }

        private void Mess2(int value)
        {
            MessageBox.Show("Item=" + value.ToString());
        }
    }

2. There are much better practices.

            String[] names = { "Jeff", "Kristin", "Aidan", "Grant", "HaifengCai" };
            Char charToEnd = 'a';
            names = Array.FindAll(names, name => name.IndexOf(charToEnd) >= 0);
            names = Array.ConvertAll(names, name => name.ToUpper());
            Array.ForEach(names, Console.WriteLine);