5-6判斷式與迴圏

 int keyIn = JOptionPane.showInputDialog(null, "請輸入字母\n 1:快餐 \n  2:麵 \n 3:烤肉").trim().charAt(0);

 switch (keyIn) {

  case 49:

        System.out.println("今天吃快餐");

break;

 case 50:

        System.out.println("今天吃麵");

break;

 case 51:

System.out.println("今天烤肉");

break;

 default:

  System.out.println("今天吃飯");

 }