this.button1.Click += (_sender, _e) => { System.Windows.Forms.MessageBox.Show(_sender.ToString()); }; delegate int del(int i); static void Main(string[] args) { del myDelegate = x => x * x; int j = myDelegate(5); //j = 25 } using System.Linq.Expressions; namespace ConsoleApplication1 { class Program { static void Main(string[] args) { Expression<del> myET = x => x * x; [...]