C # lambda expressions and expression trees

usingSystem;usingSystem.Collections.Generic;usingSystem.Data.SqlClient;usingSystem.Linq;usingSystem.Text;usingSystem.Threading.Tasks;namespaceSrljcshap. Delegate. demo{Delegate voidStringprocessor (stringInput);//declaring delegate types     Public classPerson {stringname;  PublicPerson (stringName) {             This. Name =Name; }        //declaring a compatible instance method         Public voidSay (stringMSG) {Console.WriteLine ("{0} says: {1}", name, MSG); }    }     Public classBackground {//declaring a compatible static method         Public Static voidNote (stringNote) {Console.WriteLine ("({0})", note); }           }}

usingSystem;usingSystem.Collections.Generic;usingSystem.ComponentModel;usingSystem.Linq;usingSystem.Linq.Expressions;usingSystem.Text;usingSystem.Windows.Forms;namespaceSrljcshap. A lambda expression and an expression tree. demo{classProgram {Static voidMain (string[] args) {Func<string,int>returnlength; Returnlength= Text =text.            Length; Console.WriteLine (Returnlength ("Hello")); #regionUse lambda expressions to process a list of moviesvarFilms =NewList<film>            {                Newfilm{name="Dragon in the lake", year=1999},                Newfilm{name="Violent Neighborhoods", year= .},                Newfilm{name="Western Tour", year=1998},                NewFilm{name="Nanjing Nanjing", year=1985},                NewFilm{name="The Wizard of Oz", year=1935},                NewFilm{name="Apple", year= the}            }; Action<Film> print =film= Console.WriteLine ("Name={0},year={1}", Film.name, film.year);//to create a reusable list print delegateFilms. ForEach (print);//Print the original listFilms. FindAll (f= F.year <1990). ForEach (print);//to create a filtered listFilms. Sort ((f1, F2) = F1.name.CompareTo (F2.name));//sort the original listFilms.            ForEach (print); #endregion            #regionUse a lambda expression to record an eventButton btn=NewButton {Text ="Click Me" }; Btn. Click+ = (src, e) = Log ("Click", SRC, e); Btn. KeyPress+ = (src, e) = Log ("KeyPress", SRC, e); Btn. MouseClick+ = (src, e) = Log ("MouseClick", src,e); Form frm=NewForm {AutoSize =true, Controls ={BTN}};            Application.Run (frm); #endregion            #regionA very simple expression treeExpression First= Expression.constant (2); Expression Second= Expression.constant (3); Expression Add=Expression.add (first, second);            Console.WriteLine (add); #endregionConsole.readkey (); }        Static voidLog (stringTitleObjectsender, EventArgs e) {Console.WriteLine ("event:{0}", title); Console.WriteLine ("sender{0}", sender); Console.WriteLine ("arguments:{0}", E.gettype ()); foreach(PropertyDescriptor propinchtypedescriptor.getproperties (E)) {                stringName =Prop.                DisplayName; ObjectValue =Prop.                GetValue (e); Console.WriteLine ("{0}={1}", name, value); }        }    }}

C # lambda expressions and expression trees