Question

public static public static void main(String[] args) {
    System.out.print("Enter the number of student names to input: ");
    int studentNum = new Scanner(System.in).nextInt();
    String students[ ] = new String[studentNum];
    for(int i = 0; i<studentNum; i++){
        students[ i ] = inputStudent(i+1);
    }
}

public static String[] inputStudent(int i) {
    String studentNum[] = new String[i];
    for(int a=0; a<i; a++) {
        System.out.print("Enter student name"+(a+1)+": ");
        studentNum[a]=new Scanner(System.in).nextLine();
    }
    return studentNum;
}

错误：

students[ i ] = inputStudent(i+1);

IT SAYS：

incompatible types: String[] cannot be converted to String

PS：不应修改主要功能。

Answer 1

您正在尝试将String数组分配给String

即

inputStudent(int i) 返回Array，但您尝试将Array分配给students[ i ] = inputStudent(i+1); 如 String [i]是元素String数组，它只接受String

Answer 2

将您的方法更改为此。您不能将String数组分配给String。另外，为什么循环你的方法？如果我理解正确，你想把n个学生加入学生阵列？你循环进入每个学生的主要和方法运行。

public static String inputStudent(int i) {
        System.out.print("Enter student name");
        String studentName = new Scanner(System.in).nextLine();
        return studentName;
    }

Answer 3

修改输入学生方法，使其仅返回单个学生。

var fs = require('fs');
var https = require('https');

var privateKey  = fs.readFileSync('/etc/letsencrypt/live/gamepit.nl/privkey.pem', 'utf8');
var certificate = fs.readFileSync('/etc/letsencrypt/live/gamepit.nl/fullchain.pem', 'utf8');
var ca = fs.readFileSync('/etc/letsencrypt/live/gamepit.nl/chain.pem', 'utf8');

var credentials = {key: privateKey, cert: certificate, ca: ca};

var app = require('express')();

app.use(function(req, res, next) {
        console.log('site call!', req.originalUrl);
        next();
});

app.get('/', function(req, res) {
        res.send('Hello World');
        res.end();
});

var https = https.createServer(credentials, app);

https.listen(3000,'127.0.0.1',  function() {
        console.log('running!');
});

Answer 4

你可以做的是改变：

students[ i ] = inputStudent(i+1);

到

students[ i ] = Arrays.toString(inputStudent(i + 1));

由于students是一个字符串，您无法将数组直接分配给String。通过使用Array.toString()，它将返回数组内容的表示形式为String。

再次查看您的问题，您无法修改主要问题。在这种情况下，我们可以设置inputStudent以返回String类型。

public static String inputStudent( int i )
{
    String studentNum[] = new String[i];
    for( int a = 0; a < i; a++ )
    {
        System.out.print( "Enter student name" + (a + 1) + ": " );
        studentNum[a] = new Scanner( System.in ).nextLine();
    }
    return Arrays.toString(studentNum);
}

或短而甜蜜。

public static String inputStudent( final int id )
{
    System.out.print("Enter student name at ID: "+id+": ");
    return new Scanner( System.in ).next();
}

Answer 5

由于您规定无法修改main函数，因此您必须将inputStudent函数的返回类型从String []更改为String。这意味着您必须更改在该函数中存储数据的方式。

因此，将String studentNum []更改为String studentNum，而不是为数组的每个索引请求新的用户输入，请求逗号分隔的所有输入并将它们存储在studentNum中。

根据您的标准，这是一种可行的方法。

Answer 6

我理解您要实现的内容，下面的代码将解决您的问题，每行代码都有解释。

public static void main(String[] args) throws Exception {
    System.out.print("Enter the number of student names to input: ");
    Scanner scanner = new Scanner(System.in); // get the scanner
    int numOfStudents = scanner.nextInt();    // get the number of students from user
    String [] students = new String [numOfStudents];    // create an array of string
    int studentAdded = 0;   // counter
    scanner = new Scanner(System.in); // recreate the scanner, if not it will skip the first student.
    do {
        System.out.println("Enter student name "+(studentAdded+1)+": ");
        String studentName = scanner.nextLine();    // ask for student name
        students[studentAdded] = studentName;       // add student name to array
        studentAdded++;     // add 1 to the counter
    } while (studentAdded < numOfStudents); // loop until the counter become the same size as students number
    System.out.println("students = " + Arrays.toString(students)); // and show the result
}

Answer 7

您的代码中有错误。主

中不需要for循环

public static public static void main(String[] args) {
    System.out.print("Enter the number of student names to input: ");
    int studentNum = new Scanner(System.in).nextInt();
    String students[ ] = inputStudent(studentNum);
}

public static String[] inputStudent(int i) {
    String studentNum[] = new String[i];
    for(int a=0; a<i; a++) {
        System.out.print("Enter student name"+(a+1)+": ");
        studentNum[a]=new Scanner(System.in).nextLine();
    }
    return studentNum;
}

Java - 将数组从数组方法返回到主函数

7 个答案: