如何更有效地从用户那里获取输入以确定要使用的方法 Java

Question

我正在编写一个程序来收集员工的名字、姓氏和销售数据。我的所有基础知识都运行良好，但我有 1 个问题。在我的 while 循环中，我对其进行了编程，因此如果用户输入 "add"，它将调用我在另一个 class 中创建的方法，并将他们输入的任何数字添加到员工当前的销售总额中。该代码有效，但由于某种原因，当我测试它时，我必须在它运行之前输入 "add" 两次；无论如何我可以解决这个问题吗？（我在中间遗漏了一堆代码，因为我觉得这对这个问题并不重要。）

//local constants
    final int QUIT = -1;
    final String ADD = "add";
    final String SUBTRACT = "subtract";

    //local variables
    int soldItems;
    String addition;
    String subtraction;
    String nameFirst;
    String nameLast;



    //while the input is not QUIT
    while(soldItems != QUIT)
    {

        //Clear screen then prompt the user to add or subtract
        System.out.print("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n");
        System.out.print(Util.setLeft(35, "Add or Subtract: "));
        addition = Keyboard.readString();
        subtraction = Keyboard.readString();
        System.out.print("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n");

        //if the user enters add the program will add to the employee total
        if(addition.equals(ADD))
        {
            info.addition(soldItems);

        }

        //else the program will subtract from the employee total
        else
        {
            info.subtraction(soldItems);
        }

        //Displays the employee information and prompts the user for the next sales figure
        System.out.println(info.toString());
        System.out.println();
        System.out.print(Util.setLeft(40, "Input the next Sales Figure: "));
        soldItems = Keyboard.readInt();

    }//end while

    //clear screen
    System.out.print("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n");

    //End of program message and Final employee information
    System.out.print(Util.setLeft(45, "Final Employee Information"));
    System.out.println(info.toString());

Answer 1

addition = Keyboard.readString();
subtraction = Keyboard.readString();

你不需要使用其中两个，只需使用 input = Keyboard.readString(); 然后检查输入并相应地处理它。

如何更有效地从用户那里获取输入以确定要使用的方法 Java

How to more efficiently get an input from a user to determine a method to use Java

java

subtraction

addition

while-loop