C# (CSharp) Lec122_ClassicVisitor_DoubleDispatch_ AdditionalExpression示例

示例#1

 public void Visit(AdditionalExpression ae)
 {
     sb.Append("(");
     ae.Left.Accept(this);
     sb.Append("+");
     ae.Right.Accept(this);
     sb.Append(")");
 }

示例#2

        public void Visit(AdditionalExpression ae)
        {
            ae.Left.Accept(this);
            var a = Result;

            ae.Right.Accept(this);
            var b = Result;

            Result = a + b;
        }

示例#3

        static void Main(string[] args)
        {
            var e = new AdditionalExpression(
                new DoubleExpression(3),
                new AdditionalExpression(
                    new DoubleExpression(4),
                    new DoubleExpression(7)));
            var ep = new ExpressionPrinter();

            ep.Visit(e);
            WriteLine(ep);

            var calc = new ExpressionCalculator();

            calc.Visit(e);
            WriteLine($"{ep} = {calc.Result}");

            ReadKey();
        }