Console.WriteLine("Please enter an expression to evaluate: ");
string text = Console.ReadLine();
Expression e = new Expression(text);
Console.WriteLine(e.Evaluate());
做计算器的话, the interface below is much better Console.WriteLine("Please enter an expression to evaluate: "); string text = Console.ReadLine(); Expression e = new Expression(text); Console.WriteLine(e.Evaluate()); 是不是 比 层层叠叠抽抽象象的裹脚布似的过渡设计滥用模式 简单扼