Question

我不知道我的标题是否解释清楚。我是java的新手（1周）。如果我使用某些单词或表达错误，请原谅我。的xD

我刚刚制作了自己的计算器。我没有其他来源的任何帮助，我做了很多。很高兴自己开始记住Java语法。：d

这是我制作的计算器的代码：

// Calc with the switch statement.

import java.util.Scanner;

public class Calcswitch { public static void main（String [] args）{

    // Different variables

    Scanner input = new Scanner(System.in);

    double fnum = 0;
    double snum = 0;
    double answer = 0;
    int whatOperation;

    String finalquestion = "";
    boolean calculateAgain = true; // Goes inside the while loop


    while (calculateAgain) {
    // Ask what type of calculation you want to perform.
    System.out.println("\n");
    System.out.println("Press 1 for +");
    System.out.println("Press 2 for -");
    System.out.println("Press 3 for *");
    System.out.println("Press 4 for /");

    whatOperation = input.nextInt();


    switch (whatOperation) {

    case 1:
        // Addition
        System.out.print("Enter first number:  ");
        fnum = input.nextInt();
        System.out.print("Enter second number:  ");
        snum = input.nextInt();

        System.out.print("The result is:  ");
        System.out.print(fnum + snum);
        break;

    case 2:
        // Subtraction
        System.out.print("Enter first number:  ");
        fnum = input.nextInt();
        System.out.print("Enter second number:  ");
        snum = input.nextInt();

        System.out.print("The result is:  ");
        System.out.print(fnum - snum);
        break;

    case 3:
        // Multiplication
        System.out.print("Enter first number:  ");
        fnum = input.nextInt();
        System.out.print("Enter second number:  ");
        snum = input.nextInt();

        System.out.print("The result is:  ");
        System.out.print(fnum * snum);
        break;

    case 4:
        // Division
        System.out.print("Enter first number:  ");
        fnum = input.nextInt();
        System.out.print("Enter second number:  ");
        snum = input.nextInt();

        System.out.print("The result is:  ");
        System.out.print(fnum / snum);  
        break;

        default: 
            System.out.print("You have entered an invalid number. ");
            break;

        }

    // Asks if you want to use the Calculator again
    System.out.print("\n\nDo you want to use the calculator again? Yes / No:   ");
    finalquestion = input.next();

    // If no, the string calculateAgain goes false, and exit the while loop.
    if (finalquestion.equalsIgnoreCase("no")) {


        calculateAgain = false;


    }


    }

    // After the while loop. 
    System.out.println("Thank you for using this calculator");
}

}

现在我想实现一个记录答案的简洁小功能。如果用户想要在他开始使用程序后看到他的计算，他就可以通过编写“log”或类似的东西来做到这一点。

问题是。我不确定如何记录答案。一种方法是制作大量字符串并保持空白。但是，我猜这不会很有活力。如果我有10个声明的字符串用于日志记录会发生什么，但用户已完成15次计算？它不会很好。

java是否有一种记录用户输入的方法，并以动态的方式存储它们以后容易回忆？

Answer 1

一个大字符串怎么样，为每个日志添加一个新行

String LOG = "LOG INFO";

// WHEN YOU WANT TO ADD A LOGENTRY TO YOUR LOG
String NewLogEntry = "REPLACE_WITH_YOUR_LOG_INFO";
LOG = LOG + /n + NewLogEntry;

根据请求记录计算以进行打印的计算器

1 个答案: