如何在Java中将字符串块转换为数组中的元素

我使用此代码读取input.txt文件并将其存储到名为everything的字符串中。 这是我的input.txt

1 2 10 I

3 1 11 C

1 2 19 R

1 2 21 C

1 125 C

如果我想将字符串转换为包含整数和字母的数组，我应该使用什么方法

我尝试使用打印第一行的整数10：

String file_path = "src/input.txt";
    String everything;
    BufferedReader br = new BufferedReader(new FileReader(file_path));
    try {
        StringBuilder sb = new StringBuilder();
        String line = br.readLine();

        while (line != null) {
            sb.append(line);
            sb.append(System.lineSeparator());
            line = br.readLine();
        }
        everything = sb.toString();
    } finally {
        br.close();
    }

但是它不起作用。

试试这个

如果您使用的是jdk8

到字符数组

char arry[];    
arry=everything.toCharArray();    
System.out.print(arry[4]);

到字符串数组

public static void readLines() {

    String file_path = "src/input.txt";
    ArrayList<String> lines = new ArrayList<>();

    try {
        try (Stream<String> stream = Files.lines(Paths.get(file_path))) {
            stream.forEach(lines::add);
        }
    } catch (IOException e) {
        e.printStackTrace();
    }


    String everything = "";
    for (int i = 0; i < lines.size(); i++) {
      if(lines.get(i).length()>0){ // uncomment if you don not want to remove empty lines
          everything = everything +  lines.get(i);
      }
    }


    char[] chars = everything.toCharArray();
    for (int i = 0; i <chars.length ; i++) {
        System.out.println("Char at index "+i+"; "+ chars[i]);
    }
}

老路

public static void readLines() {

    String file_path = "src/input.txt";
    ArrayList<String> lines = new ArrayList<>();

    try {
        try (Stream<String> stream = Files.lines(Paths.get(file_path))) {
            stream.forEach(lines::add);
        }
    } catch (IOException e) {
        e.printStackTrace();
    }

    String[] everything = new String[lines.size()];

    for (int i = 0; i < lines.size(); i++) {
       everything[i] = lines.get(i);
    }
}

---

为什么不使用字符串ArrayList？你的概念是零。首先尝试阅读一些关于字节和字符的资料。没有必要直接从stackoverflow获得答案。您的代码并不是解决问题的认真尝试。让我们看看你的合理尝试。

 public static void readFile() {

    ArrayList<String> allStrings = new ArrayList<>();


    String file_path = "src/input.txt";
    String everything;
    BufferedReader br = null;
    try {
        br = new BufferedReader(new FileReader(file_path));

        StringBuilder sb = new StringBuilder();
        String line = br.readLine();
        while (line != null) {
            if (line.length() > 0) {
                allStrings.add(line);
            }
            sb.append(line);
            sb.append(System.lineSeparator());
            line = br.readLine();
        }
        everything = sb.toString();


        //Convert to array
        String[] everyString = new String[allStrings.size()];
        System.out.println("Everything: " + everything);
        for (int i = 0; i < allStrings.size(); i++) {
            everyString[i] = allStrings.get(i);
        }


        //Print Array
        for (int i = 0; i < allStrings.size(); i++) {
            System.out.println("Index: " + everyString[i]);
        }

        br.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}