在android中使用Sqlite数据库

Question

如果我们已经拥有.sql格式的数据库文件，我们如何在我们的android应用程序&中使用它的数据加载这个数据？

Answer 1

我给你完整的代码中使用，PLZ回复，如果你成功

public class DataBaseHelper extends SQLiteOpenHelper{ 
private Context mycontext; 

private String DB_PATH = "/data/data/gr.peos/databases/"; 
//private String DB_PATH = mycontext.getApplicationContext().getPackageName()+"/databases/"; 
private static String DB_NAME = "BLib.sqlite";//the extension may be .sqlite or .db 
public SQLiteDatabase myDataBase; 
/*private String DB_PATH = "/data/data/" 
         + mycontext.getApplicationContext().getPackageName() 
         + "/databases/";*/ 

public DataBaseHelper(Context context) throws IOException { 
super(context,DB_NAME,null,1); 
this.mycontext=context; 
boolean dbexist = checkdatabase(); 
if(dbexist) 
{ 
    //System.out.println("Database exists"); 
    opendatabase(); 
} 
else 
{ 
    System.out.println("Database doesn't exist"); 
createdatabase(); 
} 

} 

public void createdatabase() throws IOException{ 
boolean dbexist = checkdatabase(); 
if(dbexist) 
{ 
    //System.out.println(" Database exists."); 
} 
else{ 
    this.getReadableDatabase(); 
try{ 
     copydatabase(); 
    } 
    catch(IOException e){ 
     throw new Error("Error copying database"); 
    } 
} 
} 
private boolean checkdatabase() { 
//SQLiteDatabase checkdb = null; 
boolean checkdb = false; 
try{ 
    String myPath = DB_PATH + DB_NAME; 
    File dbfile = new File(myPath); 
    //checkdb = SQLiteDatabase.openDatabase(myPath,null,SQLiteDatabase.OPEN_READWRITE); 
    checkdb = dbfile.exists(); 
} 
catch(SQLiteException e){ 
    System.out.println("Database doesn't exist"); 
} 

return checkdb; 
} 
private void copydatabase() throws IOException { 

//Open your local db as the input stream 
InputStream myinput = mycontext.getAssets().open(DB_NAME); 

// Path to the just created empty db 
String outfilename = DB_PATH + DB_NAME; 

//Open the empty db as the output stream 
OutputStream myoutput = new FileOutputStream("/data/data/gr.peos/databases/BLib.sqlite"); 

// transfer byte to inputfile to outputfile 
byte[] buffer = new byte[1024]; 
int length; 
while ((length = myinput.read(buffer))>0) 
{ 
    myoutput.write(buffer,0,length); 
} 

//Close the streams 
myoutput.flush(); 
myoutput.close(); 
myinput.close(); 

} 

public void opendatabase() throws SQLException 
{ 
//Open the database 
String mypath = DB_PATH + DB_NAME; 
myDataBase = SQLiteDatabase.openDatabase(mypath, null, SQLiteDatabase.OPEN_READWRITE); 

} 



public synchronized void close(){ 
if(myDataBase != null){ 
    myDataBase.close(); 
} 
super.close(); 
} 
//Your methods to insert view contents of database 

Answer 2

您可以使用SQLiteOpenHelper。
请参考Using SQLite Database with Android，其中用示例清楚说明。 所以，你可以db.execSQL("sql statements"):