Question

else if(digit == 2)
{
      System.out.print("Enter the name of artist : ");
      String artist=input.nextLine();  

      System.out.print("Enter the song title : ");
      String song = input.nextLine();

      System.out.print("Enter the number of week :");
      int oldWeek =input.nextInt();

      System.out.print("Enter the new number of week :");
      int newWeek =input.nextInt()
}

您好，我正在运行一个else if循环，如果用户输入2将运行以下代码，但问题似乎是在运行时它会同时运行2 System.out.println个代码。这是我输出的样本

This program will display singles that was Number one on charts 
Enter 1 or 2. 2
Enter the name of artist : Enter the song title :

Answer 1

好像你在nextInt()之前执行了nextLine()。会发生什么是nextInt()不消耗新行字符，因此下一个nextLine()将使用它。这使nextLine()被忽略了。的 For further information you could see this entry.

一种解决方案是在nextLine()之后调用nextInt()以使用换行字符：

int number = scanner.nextInt(); scanner.nextLine(); // Just to consume new-line character ...

另一个解决方案是使用nextLine()读取整数，然后用Integer.parseInt()解析它：

int number = Integer.parseInt(scanner.nextLine()); ...

用户输入无效

1 个答案: