Java 将模式写入文件

Question

我的一个程序遇到了一些问题，希望 SO 社区能提供帮助。所以我有这个程序要求用户输入一个数字。在他们输入数字后，程序将显示一系列 X。举个例子，假设用户输入 8。程序将在一行和一列中显示 8 个 x，如下所示:

XXXXXXXX                                                                           
XXXXXXXX                                                                           
XXXXXXXX                                                                                 
XXXXXXXX                                                                       
XXXXXXXX  
XXXXXXXX  
XXXXXXXX  
XXXXXXXX

我遇到的问题是我需要将其写入文件。我只能让它打印一行 X。因此，如果有人能告诉我如何制作上面的图表将打印到 squares.txt，那就太棒了。

import java.util.Scanner;
import java.io.*;
public class squareOutput {

public static void main(String[] args) throws IOException  {
    Scanner keyboard = new Scanner(System.in);
    System.out.println("Please enter a integer between 1 and 15");
    int number = keyboard.nextInt();
    while (number > 15 || number <1){
        System.out.println("Sorry, thats a invalid number");
        number = keyboard.nextInt();
    }
        keyboard.nextLine();
    keyboard.close();
    FileWriter fwriter = new FileWriter("square.txt", true);
    PrintWriter outputFile = new PrintWriter(fwriter);

        for (int r = 0; r < number; r++)
        {


            for (int c = 0; c < number; c++)
            {
                System.out.print("X");

                outputFile.print("X");
            }
            outputFile.println("");
            System.out.println("");



            outputFile.close();
        }
    }

Answer 1

outputFile.close(); 需要在 for 循环之外。您只想在所有写入完成后才关闭文件。

import java.util.Scanner;
import java.io.*;
public class squareOutput {

public static void main(String[] args) throws IOException  {
    Scanner keyboard = new Scanner(System.in);
    System.out.println("Please enter a integer between 1 and 15");
    int number = keyboard.nextInt();
    while (number > 15 || number <1){
        System.out.println("Sorry, thats a invalid number");
        number = keyboard.nextInt();
    }
        keyboard.nextLine();
    keyboard.close();
    FileWriter fwriter = new FileWriter("square.txt", true);
    PrintWriter outputFile = new PrintWriter(fwriter);

        for (int r = 0; r < number; r++)
        {


            for (int c = 0; c < number; c++)
            {
                System.out.print("X");

                outputFile.print("X");
            }
            outputFile.println("");
            System.out.println("");



            // outputFile.close(); <-- NOT HERE
        }
        outputFile.close(); // <-- HERE
    }   
}