Store, read--android application built-in folders

1. Store the data in the application's folder and read and write

The context provides two ways to open the I/O for the application folder and create a file if it does not exist

FileInputStream Openfileinputstream (String fileName);

Fileouputstream openfileoutputstream (String filename,int mode);

Mode

1. Mode_append: Append mode storage

2. Mode_private: Private mode storage, other apps cannot access

3. Mode_world_readable: Indicates that the current file can be read by another application

4. Mode_world_writeable: Indicates that the current file can be written by another application

Context provides a way to access application folders

File Getfilesdir (): Gets the absolute path of the folder

String[] FileList (): Gets all the data under the folder

DeleteFile (String fileName): Deletes the specified file under a folder

Instance

 Public classNewactivityextendsappcompatactivity {Private Static FinalString filename= "Firstsharedpreference"; @Overrideprotected voidonCreate (@Nullable Bundle savedinstancestate) {Super. OnCreate (savedinstancestate); Try{FileOutputStream fos=Openfileoutput (filename,mode_world_writeable); String Str= "I am good at Android"; byte[] bytes =str.getbytes (); Fos.write (Bytes,0, bytes.length); FileInputStream FIS=Openfileinput (FileName); InputStreamReader ISR=NewInputStreamReader (FIS); BufferedReader BR=NewBufferedReader (ISR); String Data= ""; StringBuilder SB=NewStringBuilder ();  while(data = Br.readline ())! =NULL) {sb.append (data); }        } Catch(FileNotFoundException e) {e.printstacktrace (); } Catch(IOException e) {e.printstacktrace (); }    }}

Store, read--android application built-in folders