Create a file in Android

4. Import Java.io.File;
6. Import java.io.IOException;
10. Import android.app.Activity;
12. Import Android.os.Bundle;
14. Import Android.view.Menu;
16. Import Android.view.MenuItem;
18. Import Android.widget.Toast;
24. Public class Mainactivity extends Activity {
28. @Override
30. protected void OnCreate (Bundle savedinstancestate) {
32. super.oncreate (savedinstancestate);
34. Setcontentview (R.layout.activity_main);
36. File file=new file ("/mnt/sdcard/test"); Create a file
38. if (!file.exists ()) {
40. try {
42. File.createnewfile ();
44. } catch (IOException e) {
46. //TODO auto-generated catch block
48. E.printstacktrace ();
50. }
52. }Else {
54. Toast.maketext (mainactivity. This,"created successfully!  ", Toast.length_short). Show ();
56. }
58. File.delete (); //delete files
60. }
62. }

Don't forget to add permissions in manifest:

[HTML]View PlainCopy

1. </Pre><pre class="html" name="code">< Uses-permission android:name="Android.permission.WRITE_EXTERNAL_STORAGE"/>

Note:

[Java]View PlainCopy

2. File file=this.getfilesdir (); This directory is the default data store directory for the current application (/data/data/com.example.filedemo1/files)
4. LOG.I ("Info", file.tostring ());
6. File file=this.getcachedir ();
8. //This directory is the location where the default cache file for the current application is stored (/data/data/com.example.filedemo1/cache)
10. //Put some files that are not very important in this create use
12. //If the phone is running out of memory, the system will automatically delete the data from the app's cache directory .
14. LOG.I ("Info", file.tostring ());
16. ///data/data/< Package name >app_imooc (/DATA/DATA/COM.EXAMPLE.FILEDEMO1/APP_IMOOC)
18. File file=this.getdir ("Imooc", mode_private);
20. /*mode_private
22. * As the default mode of operation, the representative file is private data and can only be accessed by the app itself, in which the content of the source file is overwritten.
24. * Mode_append
26. * Mode checks whether the file exists, appends content to the file, or creates a new file
28. * mode_world_readable
30. * Indicates that the current file can be read by another application
32. * mode_world_writeable
34. * Indicates that the current file can be written by another file
36. * */
38. LOG.I ("Info", file.tostring ());
40. File file=this.getexternalcachedir ();
42. //Can get External storage location (/mnt/sdcard/android/data/com.example.filedemo1/cache)
44. //The data in this location is the same as the built-in use
46. //If the app is uninstalled, the data will be erased automatically.
48. //If the developer does not follow this rule, do not put the data into/mnt/sdcard/android/data/com.example.filedemo1/cache
50. data will not be erased after uninstallation, resulting in so-called data garbage
52. LOG.I ("Info", file.tostring ());
    

Create a file in Android