特殊文件（Properties属性文件）

一，为啥要学特殊文件

 

二， 常用方法:读取

三，案例

import java.io.FileReader;
import java.util.Properties;
import java.util.Set;
 
public class Main {
    public static void main(String[] args) throws Exception {
        //1,创建一个键值对对象
        Properties properties =new Properties();
        System.out.println(properties);
 
        //2,加载数据到对象中去
        properties.load(new FileReader("untitled\\src\\prusidfn\\usfdc.properties"));
        System.out.println(properties);
 
        //3,操作一:根据键取值
        System.out.println(properties.getProperty("张三"));
 
        //4，操作二:遍历
        Set<String>keys = properties.stringPropertyNames();
        for (String key : keys) {
            String value = properties.getProperty(key);
            System.out.println("---->"+value);
        }
 
    }
}

 四，常用方法:写出

五，案例

import java.io.FileReader;
import java.util.Properties;
import java.util.Set;
 
public class Main {
    public static void main(String[] args) throws Exception {
        //1,创建一个键值对对象
        Properties properties =new Properties();
        System.out.println(properties);
 
        //2,加载数据到对象中去
        properties.load(new FileReader("untitled\\src\\prusidfn\\usfdc.properties"));
        System.out.println(properties);
 
        //3,操作一:根据键取值
        System.out.println(properties.getProperty("张三"));
 
        //4，操作二:遍历
        Set<String>keys = properties.stringPropertyNames();
        for (String key : keys) {
            String value = properties.getProperty(key);
            System.out.println("---->"+value);
        }
 
    }
}