java - 为什么我的 java 数组不允许用户输入每个值？

Question

这个问题已经有答案了:

Using scanner.nextLine() [duplicate] (5 个回答)

已关闭 8 年前。

代码应该要求每个数组的三个输入:(ID，然后是名称，然后是主要)。

ID 工作正常，但是当它转到名称时，它会打印出:

请输入学生姓名:请输入学生姓名:

并且该行只允许一个输入。然后它进入专业并再次正常工作。所以我最终得到了 3 个 ID、2 个名字和 3 个专业。

这是我的代码:

package STUDENT;

import java.util.Scanner;

public class StudentDisplayer {

    public static void main(String[] args) {

        long[]studentId = {11, 22, 33};
        String[] studentName = {"Value1", "Value2", "Value3"};
        String[] studentMajor = {"Value1", "Value2", "Value3"};
        Scanner inReader = new Scanner(System.in);


             /* ----------------------------------------------
            Print the information in the parallel arrays
            ---------------------------------------------- */

        for (int i = 0; i < studentId.length; i++ ){
            System.out.println("Please enter the student's id: ");
            studentId[i] = inReader.nextLong();
        }

        for (int i = 0; i < studentName.length; i++){
            System.out.println("Please enter the student's name: ");
            studentName[i] = inReader.nextLine();
        }

        for (int i = 0; i < studentMajor.length; i++){
            System.out.println("Please enter the student's major: ");
            studentMajor[i] = inReader.nextLine();
        }

        for (int i = 0; i < studentId.length; i++ )
        {
            System.out.print( studentId[i] + "\t");   
            System.out.print( studentName[i] + "\t");  
            System.out.print( studentMajor[i] + "\t");
            System.out.println();
        }
    }
}

Answer 1

发生的情况是 nextLong() 不会使用换行符 \n (当您按 Intro 时输入该字符) )。因此，在继续您的逻辑之前，您必须先消耗它:

for (int i = 0; i < studentId.length; i++ ){
    System.out.println("Please enter the student's id: ");
    studentId[i] = inReader.nextLong();
}

inReader.nextLine(); // ADD THIS

for (int i = 0; i < studentName.length; i++){
    System.out.println("Please enter the student's name: ");
    studentName[i] = inReader.nextLine();
}

注意:您可以阅读我前段时间写的这篇文章:[Java] Using nextInt() before nextLine()