action func用法記記

public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        public delegate void showMessage(string msg);

        public static void showM(string m)

        {

            MessageBox.Show(m);

        }

        public string returnM(string m)

        {

            return m;

        }

        private void button1_Click(object sender, EventArgs e)

        {

            //3

            showMessage s = new showMessage(showM);

            s("xxx");

            //1

            Action<string> action = showM;

            action("123");

            //2

            Action<string> a = X => showM(X);

            a("aaaaaaaaaa");

            //6

            Action<string> ac = (x1) =>

            {

                MessageBox.Show(x1);

            };

            ac("111111111111111");

            //6

            Action<string> ac2 = delegate(string xx){

                MessageBox.Show(xx);

            };

            ac2("222222222222");

           

            //5

            string m1 = "123";

            textBox1.Invoke((Action<string>)delegate(string m)

            {

                textBox1.Text = m;

            },m1);

            textBox1.Invoke(new Action<string>((x4) =>

            {

                textBox1.Text = x4;

            }), "aaaaax4");

 

            //4 --須要return

            Func<string, string> f = returnM;

            MessageBox.Show(f("abc"));

            //7

            Func<string> func = delegate()

            {

                return "我是Func<TResult>委託出來的結果";

            };

            MessageBox.Show(func());

            //8

            Func<string, string> funcOne = delegate(string s3)

            {

                return s3;

            };

            MessageBox.Show(funcOne("我是Func<T,TResult>委託出來的結果"));

 

            //9

            Func<string, string, string> funcTwo = delegate(string value1, string value2)

            {

                return value1 + " " + value2;

            };

            MessageBox.Show(funcTwo("xxx", "我是Func<T,TResult>委託出來的結果"));

            //10

            Func<string, string, string> ff = (x1, x2) =>

            {

                return x1 + " " + x2;

            };

            MessageBox.Show(funcTwo("xxx", "我是Func<T,TResult>委託出來的結果"));

        }

 

 

public IList<Model> ToList(DataTable dt,  Func<DataRow, Model> func)
        {
            if (dt == null || dt.Rows.Count == 0)
            {
                return null;
            }
            IList<Model> list = new List<Model>(dt.Rows.Count);
            foreach (DataRow dr in dt.Rows)
            {
                 list.Add(func(dr));
            }
            return list;
        } 
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!this.IsPostBack)
            {
                DataTable dt = newstable();
                IList<Model> list = ToList(dt, delegate( DataRow row)
                {
                    Model m = new Model();
                    m.f_id =Convert.ToInt32(row["f_id"]);
                     return m;
                });  
            }
        }

//////////

  static void Main(string[] args)
        {
            IList<String> list = new List<String>();
            list.Add("1");
            list.Add("2");
            list.Add("3");
            list.Add("4");
            list.Add("5");
            Func<String, bool> f = x => x.Equals("2");
            IList<String> list2 = filter(f, list);
        }
        static IList<String> filter(Func<String, bool> exp, IList<String> list)
        {
            return list.Where(exp).ToList();
        }

 

 

    }