如何讀取將讀取包含文本的文件。 讀取每一行並將其發送到輸出文件，並在其前加上行號

Question

該程序不會創建文件

Scanner in = new Scanner(System.in);

System.out.print("Input file: ");
String Mary = in.next();
System.out.print("Output file: ");
String outMary = in.next();

File inFile = new File ("Mary.txt");
Scanner inputFile = new Scanner(inFile);
PrintWriter outFile = new PrintWriter("Mary2.txt");

while (inputFile.hasNext())
{
  String input = in.nextLine();
  outFile.println(input);
}

我想讀取我創建的文件，並將其內容復制到每個行之前帶有行號的另一個文件中。

Answer 1

嘗試此代碼，這將創建新文件用於輸出。 請注意，這將刪除文件（如果在寫入之前已存在）

           File inFile = new File("Mary.txt");
            Scanner inputFile = new Scanner(inFile);

          try(BufferedWriter bw = new BufferedWriter(new FileWriter(new File("Mary2.txt")))) {
              int i=0;
              while (inputFile.hasNext()) {
                  String input = inputFile.next();
                  bw.write(i+"\\ ");
                  i++;
              }
              bw.flush();
          }