简单的委托（Simple Delegate）

namespace delegate
{
    delegate double DoubleOp(double x);

    class Program
    {
        static void Main()
        {
            DoubleOp[] operations =
            {
                 MathOperations.MultiplyByTwo,
                 MathOperations.Square
            };

            DoubleOp doubleOp = new DoubleOp(MathOperations.Square);
        }
    }