public class UserDAO {
private DBOpenHelper helper;
//写入 ,不然会是出错,是空指针
public UserDAO(Context context){
helper=new DBOpenHelper(context);
}
/**
* 添加用户信息
*/
public void add(User user){
SQLiteDatabase db=helper.getWritableDatabase();
String sql="Insert into u_user(_id,name,age,tall) values(?,?,?,?)";
db.execSQL(sql, new Object[]
{
user.getId(),user.getName(),user.getAge(),user.getTall()
}
);
db.close();
}
/**
* 删除用户信息
*/
public void delete(Integer...id){
if(id.length>0){
StringBuffer sb=new StringBuffer();
for(int i=0;i<id.length;i++){
sb.append("?").append(",");
}
sb.deleteCharAt(sb.length()-1);
SQLiteDatabase database=helper.getWritableDatabase();
String sql="delete from u_user where _id in ("+sb+")";
database.execSQL(sql, (Object[])id);
}
}
/**
* 删除表里的全部数据
*/
public void delelteall(){
SQLiteDatabase database=helper.getWritableDatabase();
String sql = "delete from u_user";
database.execSQL(sql);