IO之字节流与字符流，为什么两种方法输出都乱码了？

Question

import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.IOException;import java.io.InputStream;import java.io.Reader;public class ReaderDemo { /** * 使用字符流读取文本文件 */ public static void stringReader(){ File f = new File("E:\\测试用例.txt"); try { //构造一个字符输入流对象 Reader ri = new FileReader(f); char[] cs = new char[20]; int len = -1; StringBuffer sb = new StringBuffer(); while ((len = ri.read(cs))!=-1){ sb.append(new String(cs,0,len)); } //关闭流 ri.close(); System.out.println(sb); } catch (FileNotFoundException e) { e.printStackTrace(); }catch (IOException e) { e.printStackTrace(); } } /** * 使用字节流读取文本文件 * @param args */ public static void byteReader(){ File f = new File("E:\\测试用例.txt"); try { InputStream is = new FileInputStream(f); byte[] bytes = new byte[1024]; int len = -1; StringBuffer sb = new StringBuffer(); while ((len = is.read(bytes))!=-1){ sb.append(new String(bytes,0,len)); } is.close(); System.out.println(sb); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } public static void main(String[] args) { //byteReader(); stringReader(); }}

Answer 1

记得采纳欧
1、你检查一下你文件的保存格式是UTF8吗？    2、你看看String(byte[] bytes,      int offset,      int length,      Charset charset)你理解这个构造函数吗？new String(bytes,0,len，“utf-8”)