Java 7 Issue逐个字符读取

Question

I need to be able to manipulate each character in a string. Could someone tell me what I'm doing wrong here?

import java.io.*;

public class encryptedWrite {
    public static void main(String[] args) {
        try {
            File file = new File("code.txt");

            // if file doesnt exists, then create it
            if (!file.exists()) {
                file.createNewFile();
            }

            BufferedReader read 
                = new BufferedReader(new InputStreamReader(System.in));
            int charNumber = 0;
            String content = read.readLine();
            FileWriter fw = new FileWriter(file.getAbsoluteFile());
            BufferedWriter bw = new BufferedWriter(fw);
            String numberString = charNumber + "";
            String modCont = content.charAt(numberString);
            while (!(modCont.equals("#"))) {
                bw.write(modCont);
                charNumber++; 
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

I need to be able to output each character of content to code.txt.

Answer 1

There are a couple issues that I see. First, charAt takes a numeric argument, not a String argument. Second, you need to read inside the loop, not outside. I would replace:

    String modCont = content.charAt(numberString);
               while (!(modCont.equals("#"))) {
    bw.write(modCont);
        charNumber++; 
      }

with

while (true) {
    String modCont = (String) content.charAt(charNumber);
    if (modCont.equals("#")) {
        break;
    }
    bw.write(modCont);
    charNumber++; 
}

Answer 2

String的类方法：charAt（）以int作为参数，您正在传递String对象作为参数。