android SharedPreferences存储byte数组

存

             SharedPreferences sharedPreferences = getSharedPreferences("demo", Activity.MODE_PRIVATE);
             Editor editor = sharedPreferences.edit();
             String imageString = new String(Base64.encode(b,Base64.DEFAULT));
             editor.putString("content", imageString);
             editor.commit();
取

                 SharedPreferences sharedPreferences = getSharedPreferences("demo",Activity.MODE_PRIVATE);
                 String string = sharedPreferences.getString("content", "");
                 byte[] b = Base64.decode(string.getBytes(), Base64.DEFAULT);