SQLite(三)

//插入数据

        btn3=(Button)findViewById(R.id.btn3);

        btn3.setOnClickListener(new OnClickListener(){

           public void onClick(View v) {

              // 建立数据对象

              ContentValues values=new ContentValues();

              values.put("id", 2);

              values.put("name", "guoxu");

              SqlHelper db=new SqlHelper(SqLiteDemoActivity.this, "myhome.db");

                // 获得可写的表

               SQLiteDatabase sqlitedb=db.getWritableDatabase();

// 插入数据

               sqlitedb.insert("user", null, values);

// 关闭数据库

               db.close();

                System.out.println("data is insert");

           }

        

        });

        //更新数据

        btn4=(Button)findViewById(R.id.btn4);

        btn4.setOnClickListener(new OnClickListener(){

           public void onClick(View v) {

              // TODO Auto-generated method stub

              ContentValues values=new ContentValues();

              values.put("name", "郭旭");

              SqlHelper db=new SqlHelper(SqLiteDemoActivity.this, "myhome.db");

               SQLiteDatabase sqlitedb=db.getWritableDatabase();

               sqlitedb.update("user", values, "id=?", new String[]{"1"});

               System.out.println("data is update");

               db.close();

           }

        

        });

        //删除数据

        btn5=(Button)findViewById(R.id.btn5);

        btn5.setOnClickListener(new OnClickListener(){

           public void onClick(View v) {

              SqlHelper db=new SqlHelper(SqLiteDemoActivity.this, "myhome.db");

               SQLiteDatabase sqlitedb=db.getWritableDatabase();

               sqlitedb.delete("user", "id=?", new String[]{"2"});

               System.out.println("data is update");

               db.close();

           }

        

        });

        //查询数据

        btn6=(Button)findViewById(R.id.btn6);

        btn6.setOnClickListener(new OnClickListener(){

           public void onClick(View v) {

              // TODO Auto-generated method stub

              SqlHelper db=new SqlHelper(SqLiteDemoActivity.this, "myhome.db");

               SQLiteDatabase sqlitedb=db.getReadableDatabase();

               Cursor cursor=sqlitedb.query("user", new String[]{"id","name"},

                    nullnullnullnull, "id desc");

               StringBuffer str=new StringBuffer();

               while(cursor.moveToNext()){

               int id=cursor.getInt(cursor.getColumnIndex("id"));

               String name=cursor.getString(cursor.getColumnIndex("name"));

               str.append("id="+id);

               str.append("<br>name="+name+"<br>");

               }

               datatxt=(TextView)findViewById(R.id.datatxt);

               datatxt.setText(Html.fromHtml(str.toString()));

           }

        

        });

    }

}

原文地址:https://www.cnblogs.com/itfenqing/p/4429526.html