Question

我是Java的初学者，我有一个问题要做：问题提示用户5次输入，股票的名称，然后股票价格，然后股票的数量，我们应该计算所有股票价值的总和，我只用两个提示使用循环写，但我的问题是，在第二个提示时间循环跳过字符串输入为第二个股票名称而不是promting ...贝娄是代码：

import java.util.Scanner;
public class test1 {

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        double sharePrice =0,stockPrice = 0, temp = 0 ;
        int i = 0;
        double sum=0;
        String name;
        while (i < 2) {
            System.out.println("Enter the Name of the Stock "); 
            name = input.nextLine();

            System.out.println("Enter the Share price ");
            sharePrice = input.nextDouble();

            System.out.println("Enter the number of owned shares");
            int numberOfshares = input.nextInt();
            stockPrice = sharePrice * (double)(numberOfshares);

            sum += stockPrice;

            i++;
        }
        System.out.println("the total stockprice owned is: " + sum );
    }
}

这是我得到的输出：

  Enter the Name of the Stock 
  nestle
  Enter the Share price 
  2
  Enter the number of owned shares
  4


  Enter the Name of the Stock 
  Enter the Share price

在第二次循环中输入跳过的原因是什么？

Answer 1

根据我的评论，问题是您的代码在调用nextInt()或nextDouble()时不会处理行尾（EOL）令牌。

解决方案是在获取int和double之后使用input.nextLine()以吞下EOL令牌：

sharePrice = input.nextDouble();
input.nextLine();  // add this 

System.out.println("Enter the number of owned shares");
int numberOfshares = input.nextInt();
input.nextLine();  // add this 
stockPrice = sharePrice * (double)(numberOfshares);

Answer 2

问题是你上次打电话

int numberOfshares = input.nextInt();

在循环的第一次迭代中，您的第一次传递回车符作为下一个股票名称。你可以改用：

double sharePrice = Double.parseDouble(input.nextLine());

和

int numberOfshares = Integer.parseInt(input.nextLine());

Answer 3

您应该在阅读股票价格和股票数量后读出换行符：

public static void main(String[] args)
{
    Scanner input = new Scanner(System.in);
    double sharePrice = 0, stockPrice = 0;
    int i = 0;
    double sum = 0;
    String name;
    while (i < 2)
    {
        System.out.println("Enter the Name of the Stock ");
        name = input.nextLine();
        System.out.println("Enter the Share price ");
        sharePrice = input.nextDouble();
        // Read out the newline character after the share price.
        input.nextLine();
        System.out.println("Enter the number of owned shares");
        int numberOfshares = input.nextInt();
        // Read out the newline character after the number of shares.
        input.nextLine();
        stockPrice = sharePrice * (double) (numberOfshares);
        sum += stockPrice;
        System.out.println(String.format("Name: %s, Price: %f, Shares: %d, Total: %f",
                                         name,
                                         sharePrice,
                                         numberOfshares,
                                         stockPrice));
        i++;
    }
    System.out.println("the total stockprice owned is: " + sum);
}

请参阅上面带注释的行：

JAVA初学者帮助循环中需要字符串输入

3 个答案: