使用|| 在交换机的情况下？

因此,对于Java Fundamentals的大学实验室,我遇到了麻烦.我必须设置一个开关并在里面切换一个盒子.用户输入有3个选项,每个选项都可以用字母回答.问题是这封信被允许为大写或小写,而问题是我似乎无法弄清楚如何设置它以便一个案例允许其中任何一个.

在下面的代码中.crustType被定义为char.

请记住这是Java基础知识,我们只是学习交换机,不幸的是我们的PPT并没有解释在这种情况下该怎么做.

switch (crustType)
  {
     case (crustType == 'H' || crustType == 'h'):
        crust = "Hand-tossed";
        System.out.println("You have selected 'Hand-Tossed' crust for your pizza.");
        break;

     case (crustType == 'T' || crustType == 't'):
        crust = "Thin-crust";
        System.out.println("You have selected 'Thin-Crust' crust for your pizza.");
        break;

     case (crustType == 'D' || crustType == 'd'):
        crust = "Deep-dish";
        System.out.println("You have selected 'Deep-Dish' crust for your pizza.");
        break;

     default:
        crust = "Hand-tossed";
        System.out.println("You have not selected a possible choice so a Hand-tossed crust was selected.");
  }

但是我一直收到错误|| ...

97: error: incompatible types
      case (crustType == 'H' || crustType == 'h'):
                             ^   required: char   found:    boolean 
102: error: incompatible types

Christian.. 10

使用:

case 'H':
case 'h':
    ...
    break;
case 'T':
case 't':
    ...
    break;

代替.既然类型crustType是char,那么cases中的内容必须是char类型.当你把类似的东西

crustType == 'H'

你会得到一个错误,因为该表达式返回一个boolean.