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  • 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()));

               }

            

            });

        }

    }

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