我在Java中使用while,do-while循环创建多个文件夹时出现问题。我尝试创建文件,我没有问题,但文件夹,不同的故事。 我使用的是Scanner和BufferedReader。问题是,它的行为真的很奇怪。 如果我输入至少3个文件夹名称,它通常只创建第一个,或者跳过第二个并创建第一个和第三个。最后它不会接受我的"退出"作为我的终点,它只会创建名为"退出"并等待更多的输入。 我已经在谷歌搜索但没有找到任何帮助我的东西。这是代码,(案例AddShelf):`包库;
public class Administrator {
public static String help_msg = "[ Main Menu ]\r\n\r\nAddBook\r\nRemoveBook\r\nBookInfo\r\nAddShelf\nRemoveShelf\r\nShelfInfo";
private static final DateFormat sdf = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss");
public static void main(String[] args)throws IOException {
Date date = new Date();
System.out.println(sdf.format(date));
System.out.println("Welcome to my book library\r\n\r\n"+"ADMINISTRATOR\r\n\r\n"+help_msg+"\r\n");
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String operate = br.readLine();
do {
switch(operate) {
case"AddBook":
//chose shelf,add new book
case"RemoveBook":
//chose shelf,remove book
case"BookInfo":
//chose shelf,chose book,show book info
case"AddShelf":
try {
System.out.println("Enter the name of the shelf:");
Scanner sc = new Scanner(System.in);
String files = sc.nextLine();
do {
File dir = new File("D:\\admir\\MyBookLibrary\\"+files);
dir.mkdirs();
}while(!"Exit".equals(sc.next()));
System.out.println("Shelf added successfully!");
}catch(Exception e) {
System.err.println("Unable to create new Shelf!");
}
case"RemoveShelf":
//remove shelf
case"ShelfInfo":
//shelf info
default:
//if incorrect operation is entered,print message,back to choosing operations
}
}while(!"Exit".equals(br.readLine()));
}
}
答案 0 :(得分:0)
我检查代码做的虽然有点困难,所以我在尝试此代码时将其更改为。
import java.io.File;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Scanner;
public class Administrator {
public static String help_msg = "[ Main Menu ]\r\n\r\nAddBook\r\nRemoveBook\r\nBookInfo\r\nAddShelf\nRemoveShelf\r\nShelfInfo";
private static final DateFormat sdf = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss");
public static void main(String[] args){
Date date = new Date();
System.out.println(sdf.format(date));
System.out.println("Welcome to my book library\r\n\r\n"+"ADMINISTRATOR\r\n\r\n"+help_msg+"\r\n");
Scanner sc = new Scanner(System.in);
String operate;
while(!"Exit".equals(operate = sc.nextLine())){
switch(operate) {
case"AddBook":
//chose shelf,add new book
case"RemoveBook":
//chose shelf,remove book
case"BookInfo":
//chose shelf,chose book,show book info
break;
case"AddShelf":
try {
System.out.println("Enter the name of the shelf:");
String files;
while(!"Exit".equals(files = sc.nextLine())){
File dir = new File("D:\\admir\\MyBookLibrary\\"+files);
dir.mkdirs();
System.out.println(files+"Shelf added successfully!");
System.out.println("Enter another name of the shelf:");
}
return;
}catch(Exception e) {
System.err.println("Unable to create new Shelf!");
}
break;
case"RemoveShelf":
//remove shelf
case"ShelfInfo":
//shelf info
default:
//if incorrect operation is entered,print message,back to choosing operations
}
}
}
}