java - 创建重新检查 if 语句

Question

我正在为类(class)编写平均成绩脚本，但我不知道如何重复交叉检查部分，直到获得有效值(代码在下面列出)。运行时，如果原始输入无效，它允许我进行更正，但只执行一次。我怎样才能循环直到得到正确的响应？提前致谢!

  if (grade1 >= 0 && grade1 <= 100)
     System.out.println("First grade valid.\n");
  else
     {
        System.out.println("Grade invalid.  Re-enter first grade:");
        grade1 = kb.nextDouble();
     }

Answer 1

考虑

grade = -1;
System.out.println("Enter a grade:\n");
grade1 = kb.nextDouble();
if (grade1 >= 0 && grade1 <= 100)
{
    System.out.println("First grade valid.\n");
}
else
{
    while (grade1 < 0 || grade1 > 100)
    {
        System.out.println("Grade invalid.  Re-enter first grade:");
        grade1 = kb.nextDouble();
    }
}