Question

我正在尝试在此数组中打印学生的姓名。我不断收到一条错误消息，

[Ljava.lang.String; @ 55f96302

我声明并初始化顶部附近的名称，我正在尝试使用＆＃34; System.out.println打印它（＆＃34;学生的平均分数＆＃34; +姓名+＆＃34;是：＆＃34 +平均值）;＆＃34;但显然单独拥有名称不是解决方案。我该如何修复我的代码？

import java.util.Scanner;

public class Grades {
    //An array to hold the student names
    String[] Names = new String[6];

    //An array to hold students letter grades
    char[] LetterGrades = new char[6];

    //an array to hold each of the students test scores
    double[] Test1Scores = new double[6];
    double[] Test2Scores = new double[6];
    double[] Test3Scores = new double[6];

    void EnterData() {
        //initialize the scanner to parse the user inputs
        Scanner sc = new Scanner(System.in);

        //initialize the for loop and create iterations from 0 to 6  
        for (int i = 0; i < 6; i++) {
            //get user's name
            System.out.print("Enter the name of student " + (i + 1) + ": ");
            Names[i] = sc.next();

            //Create a while loop to get each of the students test scores
            do {
                System.out.print("Enter the score for Test 1: ");
                Test1Scores[i] = sc.nextDouble();
            } while (Test1Scores[i] < 0 || Test1Scores[i] > 100);
            do {
                System.out.print("Enter the score for Test 2: ");
                Test2Scores[i] = sc.nextDouble();
            } while (Test2Scores[i] < 0 || Test2Scores[i] > 100);
            do {
                System.out.print("Enter the score for Test 3: ");
                Test3Scores[i] = sc.nextDouble();
            } while (Test3Scores[i] < 0 || Test3Scores[i] > 100);
            System.out.println("Testscores: " + Test1Scores[i] + " " + Test2Scores[i] + " " + Test3Scores[i]);
        }
    }

    void GetNames() {
        for (int i = 0; i < 6; i++)
            System.out.println((i + 1) + ". " + GetName(i + 1));
    }

    String GetName(int studNumber) {
        return (Names[studNumber - 1]);
    }
    //prints the 3 test scores of the student
    void GetTestScores(int studNumber) {
        System.out.println(GetTestScore(studNumber, 1) + " ");
        System.out.println(GetTestScore(studNumber, 2) + " ");
        System.out.println(GetTestScore(studNumber, 3) + " ");
    }

    double GetTestScore(int studNumber, int testNumber) {
        if (testNumber == 1)
            return (Test1Scores[studNumber - 1]);
        else if (testNumber == 2)
            return (Test2Scores[studNumber - 1]);
        else if (testNumber == 3)
            return (Test3Scores[studNumber - 1]);
        return 0;
    }
    //calculate the average test score
    double GetAverageScore(int studNumber) {
        double avg = (Test1Scores[studNumber - 1] + Test2Scores[studNumber - 1] + Test3Scores[studNumber - 1]) / 3;
        System.out.println("The average scores of student "+Names+" is:"+avg);
        return avg;
    }

    void GetLetterGrades() {
        for (int i = 1; i <= 6; i++) {
            System.out.println("The letter grade of student " + (i) + " is: " + GetLetterGrade(i));
        }
    }

    char GetLetterGrade(int studNumber) {
        double sum = Test1Scores[studNumber - 1] + Test2Scores[studNumber - 1] + Test3Scores[studNumber - 1];
        char letterGrade;
        if (sum / 3 >= 90)
            letterGrade = 'A';
        else if (sum / 3 >= 80)
            letterGrade = 'B';
        else if (sum / 3 >= 70)
            letterGrade = 'C';
        else if (sum / 3 >= 60)
            letterGrade = 'D';
        else
            letterGrade = 'F';
        return letterGrade;
    }

    void GetClassAverage() {
        double sum = 0.0;
        for (int i = 0; i < 6; i++)
            for (int j = 0; j < 3; j++)
                sum += GetTestScore(i + 1, j + 1);
        System.out.println("The average of the class is: " + sum / 18);
    }

    void GetTopGrade() {
        char letterGrade;
        double top = GetAverageScore(1);
        for (int i = 2; i <= 6; i++)
            if (GetAverageScore(i) > top)
                top = GetAverageScore(i);
        if (top >= 90)
            letterGrade = 'A';
        else if (top >= 80)
            letterGrade = 'B';
        else if (top >= 70)
            letterGrade = 'C';
        else if (top >= 60)
            letterGrade = 'D';
        else
            letterGrade = 'F';
        System.out.println("The top score of the class is: " + letterGrade);
    }
}

Answer 1

您要打印的是学生的名字，但变量Names是它的数组类型。

所以你想做的就是改变

System.out.println("The average scores of student "+Names+" is:"+avg);

到

System.out.println("The average scores of student "+Names[studNumber]+" is:"+avg);

此。

Answer 2

在您提供的示例中，您将打印数组本身而不是数组中的值。您需要遍历数组'Names'并单独打印出每个值。

for( int i = 0;i<Names.length;i++){
    System.out.println(Names[i]);
}

Answer 3

如果你想在字符串中打印学生姓名，例如学生a，b，c的平均分数是：100

您可以通过迭代元素并使用该方法创建一个返回输入String数组的逗号分隔值的方法： “学生的平均分数”+ csvStringMethod（姓名）+“是：”+ avg

Answer 4

感谢您的帮助，但我能够使用以下内容：

System.out.println("The average scores of student " + Names[studentNumber - 1] + " is:"+avg);

从Java中的数组中获取输入变量

4 个答案: