[移动开发]2021-09-28

**

Andriond Studio APP 在手机读写文件**

注意点：需要在Activity中引用并 注入上下文

package com.xwsoft.zthx.driver.common.util;

import android.app.Application;
import android.content.Context;
import org.jsoup.helper.StringUtil;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Properties;

/**
 * http 工具类
 */
public class PropertiesUtil extends Application {

    /**
     * 根据配置文件中的key获取value (当获取不到值赋予默认值)
     *
     * @return
     */
    public  String getPropertyByKey(String key) {
        Properties props = new Properties();
        try {
            String fileName = "face.properties";
            props.load(getApplicationContext().getAssets().open(fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
        String value = props.getProperty(key.trim());
        if (StringUtil.isBlank(value)) {
            value = "defaultValue";
        }
        return value.trim();
    }



    //初始化配置文件
    //最好放在Application中，初始化。
    public  String initProperties() {
        Properties props = new Properties();
        try {
            String fileName = "face.properties";
            props.load(getApplicationContext().getAssets().open(fileName));
            props.load(getApplicationContext().getAssets().open("face.properties"));
            FileOutputStream out = getApplicationContext().openFileOutput("face.properties", Context.MODE_PRIVATE);
            props.store(out, null);
        } catch (Exception e) {
            e.printStackTrace();
            return "修改配置文件失败!";
        }
        return "设置成功";
    }


    /**
     *
     * @return
     */
    public  void setProperty(String key,String value) {
        if(!value.isEmpty()){
            try {
                String path = "/assets/";
                String fileName = "face.properties";
                File file = new File(path, fileName);
                OutputStream fos = new FileOutputStream(file);
                Properties props = new Properties();
                props.setProperty(key,value);
                props.store(fos, "Update '" + key + "' value");
            } catch (IOException e) {
                System.err.println("属性文件更新错误");
            }
        }
    }
}