Java字符流的读写

迈不过友情╰ 2021-09-30 00:54 306阅读 0赞

**一 代码**

import java.io.* ;
    
    public class CharDemo
    {
        public static void main(String args[])
        {
            File f = new File("d:\\temp.txt") ;
            Writer out = null ;
            try
            {
                out = new FileWriter(f) ;
            }
            catch (IOException e)
            {
                e.printStackTrace() ;
            }
            // 声明一个String类型对象
            String str = "Hello World!!!中国" ;
            try
            {
                // 将str内容写入到文件之中
                out.write(str) ;
            }
            catch (IOException e1)
            {
                e1.printStackTrace() ;
            }
            try
            {
                out.close() ;
            }
            catch (IOException e2)
            {
                e2.printStackTrace() ;
            }
    
            // 以下为读文件操作
            Reader in = null ;
            try
            {
                in = new FileReader(f) ;
            }
            catch (FileNotFoundException e3)
            {
                e3.printStackTrace() ;
            }
            // 开辟一个空间用于接收文件读进来的数据
            char c1[] = new char[1024] ;
            int byteCount = 0 ;
            try
            {
                // 将c1的引用传递到read()方法之中，同时此方法返回读入数据的个数
                byteCount = in.read(c1) ;
            }
            catch (IOException e4)
            {
                e4.printStackTrace() ;
            }
            try
            {
                in.close() ;
            }
            catch (IOException e5)
            {
                e5.printStackTrace() ;
            }
            // 将字符数组转换为字符串输出
            System.out.println(new String(c1, 0, byteCount)) ;
        }
    }

**二 运行**

Hello World!!!中国

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70][]

在utral Edit下查看文件的二级制内容（CTRL+H）

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70 1][]

**三 说明**

中的utf-8编码：%E4%B8%AD

国的utf-8编码：%E5%9B%BD

字母A的几种编码

ascii: 0x41 unicode: 0x0041 utf-8: 0x41

**四 编码查看工具**

[http://tool.chinaz.com/tools/unicode.aspx][http_tool.chinaz.com_tools_unicode.aspx]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20190720192649788.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw==,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20190720192710406.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw==,size_16,color_FFFFFF,t_70
[http_tool.chinaz.com_tools_unicode.aspx]: http://tool.chinaz.com/tools/unicode.aspx