Java使用IO流读取TXT文件

╰+攻爆jí腚メ 2022-04-18 03:41 260阅读 0赞

## 通过BufferedReader读取TXT文件 ##

window系统默认的编码是GBK，而IDE的编码多数为UTF-8，如果没有规定new InputStreamReader(new FileInputStream(file),“GBK”)为GBK会出现读取内容乱码。

//文件路径
    		String filePath="C:/Users/Admin/Desktop/products.txt";
            File file=new File(filePath);
            BufferedReader reader = null;
            String tempString = null;
            int line =1;
            try {
                // System.out.println("以行为单位读取文件内容，一次读一整行：");
                reader = new BufferedReader(new InputStreamReader(new FileInputStream(file),"GBK"));
                while ((tempString = reader.readLine()) != null) {
                    System.out.println("Line"+ line + ":" +tempString)；
                    line ++ ;
                }
                reader.close();
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }finally{
                if(reader != null){
                    try {
                        reader.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }

## 读取TXT文件并保持在List集合 ##

TXT文件内容  
商品 价格 类型 数量  
![在这里插入图片描述][20181107234618916.png]  
创建Product对象

public class Product{
        private int    id;
        private String name;
        private int    price;
        private char type;
        private int    count;

//将txt文件中的产品对象读取出来并且封装成集合对象
        private static  List<Product> getProductFromTxt(){
            List<Product> list=new ArrayList<>();
            String filePath="C:/Users/Admin/Desktop/products.txt";
            File file=new File(filePath);
            BufferedReader reader = null;
            String content = null;
            int line =1;
            try {
               // System.out.println("以行为单位读取文件内容，一次读一整行：");
                reader = new BufferedReader(new InputStreamReader(new FileInputStream(file),"GBK"));
                while ((content = reader.readLine()) != null) {
                    //System.out.println("Line"+ line + ":" +tempString);
                    String[] arra=content.split(",");
                    Product product=new Product();
                    product.setId(line);
                    product.setName(arra[0]);
                    product.setPrice(Integer.parseInt(arra[1]));
                    char[] ch=arra[2].toCharArray();
                    product.setType(ch[0]);
                    product.setCount(Integer.parseInt(arra[3]));
                    list.add(product);
                    line ++ ;
                }
                reader.close();
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }finally{
                if(reader != null){
                    try {
                        reader.close();
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
            }
        return list;
        }

其中包含了String转char

char[] ch=str.toCharArray();
     product.setType(ch[0]);

[20181107234618916.png]: /images/20220418/9bd7c3ae014d4b87ac6dddd88969c366.png