I am developing an application in which I am using database and storing that database file with .db extention into sdcard .. Now I want to convert this "db file into .csv", so that the user can open that .csv file and can easily able to see all its data...
可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效,请关闭广告屏蔽插件后再试):
问题:
回答1:
Hey I got the answer of my own question: I downloaded a library OpenCSV and added opencsv.jar file into my application and the below code:
class ExportDatabaseCSVTask extends AsyncTask<String, Void, Boolean>{
private final ProgressDialog dialog = new ProgressDialog(MyDatabaseActivity.this);
// can use UI thread here
@Override
protected void onPreExecute(){
this.dialog.setMessage("Exporting database...");
this.dialog.show();
}
// automatically done on worker thread (separate from UI thread)
protected Boolean doInBackground(final String... args){
File dbFile=getDatabasePath("mydb.db");
// DbClass DBob = new DbClass(MyDatabaseActivity.this);
File exportDir = new File(Environment.getExternalStorageDirectory(), "");
if (!exportDir.exists()) {
exportDir.mkdirs();
}
File file = new File(exportDir, "excerDB.csv");
try {
file.createNewFile();
CSVWriter csvWrite = new CSVWriter(new FileWriter(file));
//SQLiteDatabase db = DBob.getReadableDatabase();
Cursor curCSV=mydb.rawQuery("select * from " + TableName_ans,null);
// Cursor curCSV = db.rawQuery("SELECT * FROM table_ans12",null);
csvWrite.writeNext(curCSV.getColumnNames());
while(curCSV.moveToNext()){
String arrStr[] ={curCSV.getString(0),curCSV.getString(1)};
/*curCSV.getString(2),curCSV.getString(3),curCSV.getString(4)*/
csvWrite.writeNext(arrStr);
}
csvWrite.close();
curCSV.close();
return true;
} catch(SQLException sqlEx) {
Log.e("MainActivity", sqlEx.getMessage(), sqlEx);
return false;
} catch (IOException e) {
Log.e("MainActivity", e.getMessage(), e);
return false;
}
}
// can use UI thread here
@Override
protected void onPostExecute(final Boolean success) {
if (this.dialog.isShowing()) {
this.dialog.dismiss();
}
if (success) {
Toast.makeText(MyDatabaseActivity.this, "Export successful!", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(MyDatabaseActivity.this, "Export failed", Toast.LENGTH_SHORT).show();
}
}
}