文件保存方式：固定路径、根据上下文自动存储、将文件保存到sd卡

1.固定路径保存：

 1            // 将文件保存到固定路径中
 2                try {
 3             String result = username + "##" + userpwd;
 4             // 创建file类指定我们要把数据存储的位置
 5             File file = new File("data/data/com.hollysource.login/info.txt");
 6             // 创建一个文件的输出流
 7             FileOutputStream fos = new FileOutputStream(file);
 8             fos.write(result.getBytes());
 9             fos.close();
10             return true;
11         } catch (Exception e) {
12             // TODO: handle exception
13             e.printStackTrace();
14             return false;
15         
 1 // 读取保存的在固定路径中的文件
 2         try {
 3             Map<String, String> maps = new HashMap<String, String>();
 4             File file = new File("data/data/com.hollysource.login/info.txt");
 5             FileInputStream fis = new FileInputStream(file);
 6             BufferedReader buf = new BufferedReader(new InputStreamReader(fis));
 7             String content = buf.readLine(); // 读取数据
 8             
 9             // 切割字符串
10             String[] splits = content.split("##");
11             String name = splits[0];
12             String pwd = splits[1];
13             
14             maps.put("name", name);
15             maps.put("pwd", pwd);
16             fis.close();
17             return maps;
18             
19         } catch (Exception e) {
20             // TODO Auto-generated catch block
21             e.printStackTrace();
22             return null;
23         }

2.根据上下文自动存储文件

 1 // 根据上下文保存
 2     public static boolean saveInfo(Context context,  String username,String userpwd){
 3         try {
 4             
 5 //            String path = context.getFilesDir().getPath();
 6             
 7             String result = username + "##" + userpwd;
 8             // 创建file类指定我们要把数据存储的位置
 9 //            File file = new File("data/data/com.hollysource.login/info.txt");
10 //            File file = new File(path,"info.txt");
11 //            // 创建一个文件的输出流
12 //            FileOutputStream fos = new FileOutputStream(file);
13             FileOutputStream fos = context.openFileOutput("infoo.txt", 0);
14             fos.write(result.getBytes());
15             fos.close();
16             return true;
17         } catch (Exception e) {
18             // TODO: handle exception
19             e.printStackTrace();
20             return false;
21         }
22     }
 1 // 根据上下文读取
 2     public static Map<String,String>readInfo (Context context){
 3         try {
 4             Map<String, String> maps = new HashMap<String, String>();
 5 //            String path = context.getFilesDir().getPath();
 6 //            File file = new File(path,"info.txt");
 7 //            FileInputStream fis = new FileInputStream(file);
 8             FileInputStream fis = context.openFileInput("infoo.txt");
 9             BufferedReader buf = new BufferedReader(new InputStreamReader(fis));
10             String content = buf.readLine(); // 读取数据
11             
12             // 切割字符串
13             String[] splits = content.split("##");
14             String name = splits[0];
15             String pwd = splits[1];
16             
17             maps.put("name", name);
18             maps.put("pwd", pwd);
19             fis.close();
20             return maps;
21             
22         } catch (Exception e) {
23             // TODO Auto-generated catch block
24             e.printStackTrace();
25             return null;
26         }

     context是调用方法时传的上下文：MainActivity.this；

3.将文件保存到sd卡中：

1>.判断sd的状态：

1              // 把数据保存到sd卡的时候，需要判断一下sd的状态是否可用
2              if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())) {
3                 Toast.makeText(MainActivity.this, "sd卡可用", 0).show();
4                     
5             } else {
6                 Toast.makeText(MainActivity.this,"sd卡不可用", 0).show();
7                 return;
8             }

2>.保存到sd卡：

 1     public static boolean saveInfo(String username,String userpwd){
 2         try {
 3             String result = username + "##" + userpwd;
 4             // 把数据保存在sdcard中
 5             String sdPath = Environment.getExternalStorageDirectory().getPath();
 6             File file = new File(sdPath,"haha.txt");
 7             // 创建一个文件的输出流
 8             FileOutputStream fos = new FileOutputStream(file);
 9             fos.write(result.getBytes());
10             fos.close();
11             return true;
12         } catch (Exception e) {
13             // TODO: handle exception
14             e.printStackTrace();
15             return false;
16         }
17     }

3>.读取sd卡中的文件：

 1     public static Map<String,String>readInfo (){
 2         try {
 3             Map<String, String> maps = new HashMap<String, String>();
 4             String sdPath = Environment.getExternalStorageDirectory().getPath();//获取路径
 5             File file = new File(sdPath,"haha.txt");
 6             FileInputStream fis = new FileInputStream(file);
 7             BufferedReader buf = new BufferedReader(new InputStreamReader(fis));
 8             String content = buf.readLine(); // 读取数据
 9             
10             // 切割字符串
11             String[] splits = content.split("##");
12             String name = splits[0];
13             String pwd = splits[1];
14             
15             maps.put("name", name);
16             maps.put("pwd", pwd);
17             fis.close();
18             return maps;
19             
20         } catch (Exception e) {
21             // TODO Auto-generated catch block
22             e.printStackTrace();
23             return null;
24         }
25     }

 

public static Map<String,String>readInfo (Context context){try {Map<String, String> maps = new HashMap<String, String>();//String path = context.getFilesDir().getPath();//File file = new File(path,"info.txt");//FileInputStream fis = new FileInputStream(file);FileInputStream fis = context.openFileInput("infoo.txt");BufferedReader buf = new BufferedReader(new InputStreamReader(fis));String content = buf.readLine(); // 读取数据// 切割字符串String[] splits = content.split("##");String name = splits[0];String pwd = splits[1];maps.put("name", name);maps.put("pwd", pwd);fis.close();return maps;} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();return null;}

posted @ 2016-12-06 23:03  庞 雷  阅读(535)  评论(0)    收藏  举报