sqlite 自动更新db

 string database = AppDomain.CurrentDomain.BaseDirectory + "\\DalianStore.db";
            string connectionString = @"Data Source=" + Path.GetFullPath(database);

            string commandText = @"SELECT * FROM Items ORDER BY payTime";

DBHelper  helper = new DBHelper(connectionString);
if (helper.LoadData(commandText, "") == true)
{
dataGridViewOrderList.DataSource = helper.DataSet.Tables[0];
}



//更新数据库
        private void dataGridViewOrderList_CellValidated(object sender, DataGridViewCellEventArgs e)
        {
            //如果改行有值发生改变
            if (dataGridViewOrderList.IsCurrentRowDirty)
            {
                DialogResult ret = MessageBox.Show("确定要更改数据吗？", "系统提示",MessageBoxButtons.OKCancel);
                if (ret == DialogResult.OK)
                {
                    if (helper != null)
                    {
                        helper.Save();
                    }
                }
            }//end of out if
        }

 

DBHelper

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SQLite;
using System.Data;

namespace MyStore
{
    class DBHelper
    {
        #region 变量
        private SQLiteConnection _connection = null;
        private string _connectionString = "";
        private SQLiteDataAdapter _dataAdapter = null;
        private DataSet _dataSet = null;
        private string _fieldNameID = "";
        

        // The DataSet is filled with the methode LoadDataSet
        public DataSet DataSet
        {
            get { return _dataSet; }
        }
        #endregion

        #region 构造函数
        public DBHelper(string connectionString)
        {
            _connectionString = connectionString;
        }
        #endregion 

        public bool LoadData(string commandText, string opt)
        {
            bool ret = true;
            _fieldNameID = opt;

            try
            {
                _connection = new SQLiteConnection(_connectionString);
                _connection.Open();

                _dataAdapter = new SQLiteDataAdapter(commandText, _connection);

                _dataAdapter.RowUpdated += dataAdapter_RowUpdated;
                _dataSet = new DataSet();

                SQLiteCommandBuilder commandBuilder = new SQLiteCommandBuilder(_dataAdapter);
                _dataAdapter.InsertCommand = commandBuilder.GetInsertCommand();
                _dataAdapter.DeleteCommand = commandBuilder.GetDeleteCommand();
                _dataAdapter.UpdateCommand = commandBuilder.GetUpdateCommand();

                _dataAdapter.Fill(_dataSet);

                return true;

            }
            catch (SQLiteException)
            {
                ret = false;
            }
            finally
            {
                _connection.Close();
            }
            return ret;
        }

        public bool Load(string commandString)
        {
            return LoadData(commandString,"");
        }

        public bool Save()
        {
            bool ret = true;
            try
            {
                _connection.Open();
                _dataAdapter.Update(_dataSet);
                ret = true;
            }
            catch (SQLiteException)
            {
                ret = false;
            }
            finally
            {
                _connection.Close();
            }
            return ret;
        }

        //在这个事件里面做一些特别的判断
        void dataAdapter_RowUpdated(object sender, System.Data.Common.RowUpdatedEventArgs e)
        { 
            
        }
    }
}