文件读写

来源：互联网发布：最简单的编程软件编辑：程序博客网时间：2024/05/11 20:55

1.sdcard文件、自己应用包内部的文件和别的应用包的文件的读取

/*******************************************************************
   * 0获取别的apk内部的文件
   * 1.获取sdcard的文件
   * 2.获取自己内部的文件
   *
   * *******************************************************************/
   private String readFileData(String fileName,int num){

   String res=null;

   try{
   FileInputStream fin=null;

   if(num==0)
   {
   File file = new File(fileName);
   // FileInputStream fin = openFileInput(file);
   fin = new FileInputStream(file);
   Log.v(m_log,"read ID from other apk inside files\n");
   }
   else if(num==1)
   {
   fin = new FileInputStream(fileName);
   Log.v(m_log,"read ID from SDCARD files\n");

   }
   else if (num==2)
   {

   fin = localcontext.openFileInput(fileName);
   Log.v(m_log,"read ID from APK inside files\n");

   }
   else
   {
   /*****其他的情况************/
   Log.v(m_log,"not support this type read file \n");
   }

   if(fin==null)
   return null;

   int length = fin.available();

   byte [] buffer = new byte[length];

   fin.read(buffer);

   res = EncodingUtils.getString(buffer, "UTF-8");

   fin.close();

   Log.v(m_log,"read files sucess\n");
   }

   catch(Exception e){
   Log.v(m_log,"error in read files \n");
   //e.printStackTrace();

   }

   String data=decodeAndcheck(res);

   return data;

   }

2.写sd卡文件和写文件到应用自己的内部包

/*******************************************************************
   * 0写到apk内部的文件
   * 1.写到sdcard的文件
   *
   * *******************************************************************/
private static boolean writeFileData(Context context,String fileName,String message,int num)
{

   boolean res=false;
   String encode_message=null;
   String writemessage=null;

if(message==null)
return false;

// int Stringhash=message.hashCode();

// encode_message=encodedata(message);
// writemessage=encode_message+":"+Stringhash;

   try{
   FileOutputStream fout=null;
      if(num==0)
      {
   fout =context.openFileOutput(fileName, Context.MODE_WORLD_READABLE);
   Log.v(m_log,"write file to inside apk package \n");
      }
      else if(num==1)
      {

      fout = new FileOutputStream(fileName);
      Log.v(m_log,"write file to sdcard \n");

      }
      else
      {
        /*************************/
        Log.v(m_log,"not support this type write file to sdcard \n");
      }

      if(fout==null)
        return false;

   byte [] bytes = message.getBytes();

   fout.write(bytes);

   fout.close();
   res=true;
   Log.v(m_log,"write file sucess \n");

   }

   catch(Exception e){

   Log.v(m_log,"error in write file to apk \n");
   e.printStackTrace();

   }

  return res;
   }

3.System.loadLibrary的失败被接受的时间是UnsatisfiedLinkError；