把txt文件中的字符按照一行一行读出,用BufferedReader类的readLine()函数
下一次写时换一行写，用BufferedWriter的newLine()函数
我给你个例子，你看看吧。
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
public class Test111 {
public static void main(String[] args) throws Exception{
String readFile="e.txt";
String writeFile="o.txt";
BufferedReader in = new BufferedReader(new InputStreamReader(new FileInputStream(readFile)));//读取文件所在路径
BufferedWriter out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(writeFile)));//写入文件所在路径
String input=null;
while((input=in.readLine())!=null){
String str[]=input.split(":");
out.write(str[1]);
out.newLine();
out.flush();
}
System.out.println(readFile+"文件处理完毕!输出文件"+writeFile);
out.close();
in.close();
}
}
运行结果：
e.txt文件内容
name:mmm
id:12312
address: asdad
o.txt文件内容
mmm
12312
asdad