Question

如何使用Java在Array中获取用户输入？即我们不是在我们的程序中自己初始化它，但用户将给它的价值。请指导!!

Answer 1

这是一个简单的代码，它从stdin读取字符串，将其添加到List<String>，然后使用toArray将其转换为String[]（如果您真的需要使用数组。）

import java.util.*;

public class UserInput {
    public static void main(String[] args) {
        List<String> list = new ArrayList<String>();
        Scanner stdin = new Scanner(System.in);

        do {
            System.out.println("Current list is " + list);
            System.out.println("Add more? (y/n)");
            if (stdin.next().startsWith("y")) {
                System.out.println("Enter : ");
                list.add(stdin.next());
            } else {
                break;
            }
        } while (true);
        stdin.close();
        System.out.println("List is " + list);
        String[] arr = list.toArray(new String[0]);
        System.out.println("Array is " + Arrays.toString(arr));
    }
}

另见：

Answer 2

package userinput;

import java.util.Scanner;

public class USERINPUT {

    public static void main(String[] args) {

        Scanner input = new Scanner(System.in);

        //allow user  input;
        System.out.println("How many numbers do you want to enter?");
        int num = input.nextInt();

        int array[] = new int[num];

        System.out.println("Enter the " + num + " numbers now.");

        for (int i = 0 ; i < array.length; i++ ) {
           array[i] = input.nextInt();
        }

        //you notice that now the elements have been stored in the array .. array[]

        System.out.println("These are the numbers you have entered.");
        printArray(array);

        input.close();

    }

    //this method prints the elements in an array......
    //if this case is true, then that's enough to prove to you that the user input has  //been stored in an array!!!!!!!
    public static void printArray(int arr[]){

        int n = arr.length;

        for (int i = 0; i < n; i++) {
            System.out.print(arr[i] + " ");
        }
    }

}

Answer 3

import java.util.Scanner;

class bigest {
    public static void main (String[] args) {
        Scanner input = new Scanner(System.in);

        System.out.println ("how many number you want to put in the pot?");
        int num = input.nextInt();
        int numbers[] = new int[num];

        for (int i = 0; i < num; i++) {
            System.out.println ("number" + i + ":");
            numbers[i] = input.nextInt();
        }

        for (int temp : numbers){
            System.out.print (temp + "\t");
        }

        input.close();
    }
}

Answer 4

您可以执行以下操作：

import java.util.Scanner;

public class Test {

        public static void main(String[] args) {

        int arr[];
        Scanner scan = new Scanner(System.in);
        // If you want to take 5 numbers for user and store it in an int array
        for(int i=0; i<5; i++) {
            System.out.print("Enter number " + (i+1) + ": ");
            arr[i] = scan.nextInt();    // Taking user input
        }

        // For printing those numbers
        for(int i=0; i<5; i++) 
            System.out.println("Number " + (i+1) + ": " + arr[i]);
    }
}

Answer 5

这在很大程度上取决于您打算如何接受此输入，即您的计划打算如何与用户互动。

最简单的示例是，如果要捆绑可执行文件 - 在这种情况下，用户只需在命令行上提供数组元素，就可以从应用程序的main方法访问相应的数组。

或者，如果您正在编写某种Web应用程序，则需要通过手动解析查询参数或通过服务来接受应用程序的doGet / doPost方法中的值具有提交到解析页面的HTML表单的用户。

如果是Swing应用程序，您可能需要弹出一个文本框供用户输入输入。在其他情况下，您可以从数据库/文件中读取值，这些值先前已由用户存放。

基本上，将输入作为数组读取非常简单，一旦你找到了获取输入的方法。您需要考虑运行应用程序的上下文，以及用户可能希望如何与此类应用程序进行交互，然后决定有意义的I / O体系结构。

Answer 6

**如何按用户输入接受数组

答案： -

import java.io.*;

import java.lang.*;

class Reverse1  {

   public static void main(String args[]) throws IOException {

     int a[]=new int[25];

     int num=0,i=0;

     BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

     System.out.println("Enter the Number of element");

     num=Integer.parseInt(br.readLine());

     System.out.println("Enter the array");

     for(i=1;i<=num;i++) {
        a[i]=Integer.parseInt(br.readLine());
     }

     for(i=num;i>=1;i--) {
        System.out.println(a[i]);    
     }

   }

}

Answer 7

int length;
    Scanner input = new Scanner(System.in);
    System.out.println("How many numbers you wanna enter?");
    length = input.nextInt();
    System.out.println("Enter " + length + " numbers, one by one...");
    int[] arr = new int[length];
    for (int i = 0; i < arr.length; i++) {
        System.out.println("Enter the number " + (i + 1) + ": ");
        //Below is the way to collect the element from the user
        arr[i] = input.nextInt();

        // auto generate the elements
        //arr[i] = (int)(Math.random()*100);
    }
    input.close();
    System.out.println(Arrays.toString(arr));

Answer 8

import java.util.Scanner;

类示例{

//检查字符串是否被视为整数。

public static boolean isInteger(String s){

    if(s.isEmpty())return false;

    for (int i = 0; i <s.length();++i){

        char c = s.charAt(i);

        if(!Character.isDigit(c) && c !='-')

            return false;
    }

    return true;
}

//Get integer. Prints out a prompt and checks if the input is an integer, if not it will keep asking.

public static int getInteger(String prompt){
    Scanner input = new Scanner(System.in);
    String in = "";
    System.out.println(prompt);
    in = input.nextLine();
    while(!isInteger(in)){
        System.out.println(prompt);
        in = input.nextLine();
    }
    input.close();
    return Integer.parseInt(in);
}

public static void main(String[] args){
    int [] a = new int[6];
    for (int i = 0; i < a.length;++i){
        int tmp = getInteger("Enter integer for array_"+i+": ");//Force to read an int using the methods above.
        a[i] = tmp;
    }

}

}

如何使用java在Array中获取用户输入？

8 个答案:

另见：