Question

有人可以向我解释我如何才能提出等级的条件，只能是0或更高或100或更低。我已经尝试了while循环中的语句，但是平均值不正确。我把它放在循环之外，但这似乎也不起作用。

 while (!gradeInput.equals(SENTINEL)) {

         try {
            int grade = Integer.parseInt(gradeInput);


            sum += grade;
            count++;

         }
         catch (NumberFormatException e) {
            JOptionPane.showMessageDialog(null,"Error! only numeric values.");
         }


         gradeInput = JOptionPane.showInputDialog("Enter exam grade (or -1 to end the program):");
      }

Answer 1

Sharma的评论可能更清晰，但这也应该有效：

gradeInput计算应该在循环的开头 - 而不是结束。

然后将您的验证放在循环中（如果输入有效，则只进行求和和计数）

if(grade>0 && grade <100) {
        sum += grade;
        count++;
}

然后用和/计算

计算循环外的平均值

Answer 2

 while (!gradeInput.equals(SENTINEL)) {

     try {



        int grade = Integer.parseInt(gradeInput);
if(grade==0 || grade<=100){

        sum += grade;
        count++;
}
     }
     catch (NumberFormatException e) {
        JOptionPane.showMessageDialog(null,"Error! only numeric values.");
     }


     gradeInput = JOptionPane.showInputDialog("Enter exam grade (or -1 to end the program):");
  }

Answer 3

试试这个

while (!gradeInput.equals(SENTINEL)) {
         try {
            int grade = Integer.parseInt(gradeInput);
            if(grade>=0 && grade<=100){
               sum += grade;
               count++;
            }
         }
         catch (NumberFormatException e) {
            JOptionPane.showMessageDialog(null,"Error! only numeric values.");
         }
         gradeInput = JOptionPane.showInputDialog("Enter exam grade (or -1 to end the program):");
      }

验证WHILE循环内的输入范围

3 个答案: