Android的三种数据储存

内部储存

//使用sharedPReference来保存用户名和密码//路径在data/data/com.duyi.sharedpreference/share_prefsSharedPreferences sp = getSharedPreferences("info", MODE_PRIVATE);//拿到sp的编辑器Editor ed = sp.edit();ed.putString("name", name);ed.putString("pass", pass);//提交ed.commit()

获取;

SharedPreferences sp = getSharedPreferences("info", MODE_PRIVATE);String name = sp.getString("name", "");String pass = sp.getString("pass", "");

外部储存

获得外部存储的路径Environment.getExternalStorageDirectory()

Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)

检测外部存储的状态//MEDIA_UNKNOWN：不能识别sd卡。//MEDIA_REMOVED：没有sd卡。//MEDIA_UNMOUNTED：sd卡存在，但是没有挂载。4.0之前，有卸载选项。现在已经没有了。//MEDIA_CHECKING：sd卡正在准备。//MEDIA_MOUNTED：sd卡已经挂载，可用。

获得sd卡剩余容量

File path = Environment.getExternalStorageDirectory();StatFs stat = new StatFs(path.getPath());long blockSize = stat.getBlockSize();//总块数long totalBlocks = stat.getBlockCount();//可用的块儿数long availableBlocks = stat.getAvailableBlocks();

文件流储存

 FileOutputStream  fs= null;   try {   fs=openFileOutput("count", Context.MODE_PRIVATE+Context.MODE_APPEND);   String str=name.getText()+","+age.getText()+","+ophone.getText();   fs.write(str.getBytes());   fs.flush();  } catch (FileNotFoundException e) {   // TODO Auto-generated catch block   e.printStackTrace();  } catch (IOException e) {   // TODO Auto-generated catch block   e.printStackTrace();  }finally{   try {    fs.close();   } catch (IOException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }  }

读取

FileInputStream fs=null;  try {   fs=openFileInput("count");   byte[] b=new byte[1024];   int len;   StringBuilder sb=new StringBuilder();   while((len=fs.read(b))!=-1){    sb.append(new String(b, 0,len));   }   tv.setText(sb.toString());  } catch (FileNotFoundException e) {   // TODO Auto-generated catch block   e.printStackTrace();  } catch (IOException e) {   // TODO Auto-generated catch block   e.printStackTrace();  }finally{   if (fs!=null) {    try {     fs.close();    } catch (IOException e) {     // TODO Auto-generated catch block     e.printStackTrace();    }   }  }