Android 深入研究SQLite实例（五）

写在前面的话，本文转载自http://www.eoeandroid.com/thread-82030-1-1.html

public void delete(Integer... ids){if(ids.length>0){StringBuilder sb = new StringBuilder();String[] strIds = new String[ids.length];for(int i=0 ; i < ids.length ; i++){sb.append('?').append(',');strIds[i] = String.valueOf(ids[i]);}sb.deleteCharAt(sb.length()-1);SQLiteDatabase database = dbmanger.getWritableDatabase();//参数 表名 指定条件 条件占位值database.delete("person", "personid in("+ sb + ")", strIds);}}public List getScrollData(int startResult, int maxResult){List persons = new ArrayList();SQLiteDatabase database = dbmanger.getWritableDatabase();//参数 表名 返回字段 指定条件 指定条件映射值 是否分组 分组条件 是否排序 分页条件Cursor cursor = database.query("person", new String[]{"personid", "name", "age"},null, null, null, null, "personid desc", startResult+ ","+ maxResult);while(cursor.moveToNext()){persons.add(new Person(cursor.getInt(0), cursor.getString(1), cursor.getShort(2)));}return persons;}public long getCount(){SQLiteDatabase database = dbmanger.getWritableDatabase();Cursor cursor = database.query("person", new String[]{"count(*)"}, null, null, null, null, null);if(cursor.moveToNext()){return cursor.getLong(0);}return 0;}}package eoe.demo;import java.util.ArrayList;import java.util.List;import it.bean.Person;import android.content.ContentValues;import android.content.Context;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;/*** 此类不需要基于sql语句 进行增删查改操作* 但是SQLiteDatabase对象是通过内部构造sql语句而执行操作的**/public class PersonSQLservice {private MangerDatabase dbmanger;public PersonSQLservice(Context context) {dbmanger=new MangerDatabase(context);}public void save(Person person){SQLiteDatabase database = dbmanger.getWritableDatabase();ContentValues values = new ContentValues();values.put("name", person.getName());values.put("age", person.getAge());//参数 表名 构建insert语句的正确字段 字段映射database.insert("person", "name", values);}public void update(Person person){SQLiteDatabase database = dbmanger.getWritableDatabase();ContentValues values = new ContentValues();values.put("name", person.getName());values.put("age", person.getAge());//参数 表名 更新映射关系 条件 占位符值database.update("person", values, "personid=?" , new String[]{String.valueOf(person.getPersonId())});}public Person find(Integer id){SQLiteDatabase database = dbmanger.getWritableDatabase();//执行查询 参数 表名 返回的字段 指定条件 指定条件值 是否分组 分组条件 是否排序Cursor cursor = database.query("person", new String[]{"personid", "name", "age"},"personid=?", new String[]{String.valueOf(id)}, null, null, null);if(cursor.moveToNext()){return new Person(cursor.getInt(0), cursor.getString(1), cursor.getShort(2));}return null;}