Access数据库创建、使用

<span>public</span> DataSet Query(<span>string</span><span> strSql)
        {
            </span><span>using</span> (OleDbConnection conn = <span>new</span><span> OleDbConnection(ConnectionString))
            {
                DataSet ds </span>= <span>new</span><span> DataSet();
                </span><span>try</span><span>
                {
                    conn.Open();
                    OleDbDataAdapter command </span>= <span>new</span><span> OleDbDataAdapter(strSql, conn);
                    command.Fill(ds, </span><span>"</span><span>ds</span><span>"</span><span>);
                }
                </span><span>catch</span><span> (System.Data.SqlClient.SqlException ex)
                {
                    </span><span>throw</span><span>;
                }

                </span><span>return</span><span> ds;
            }
        }

        </span><span>public</span>  <span>int</span> ExecuteSql(<span>string</span><span> strSql)
        {
            </span><span>using</span> (OleDbConnection conn = <span>new</span><span> OleDbConnection(ConnectionString))
            {
                </span><span>using</span> (OleDbCommand cmd = <span>new</span><span> OleDbCommand(strSql, conn))
                {
                    </span><span>try</span><span>
                    {
                        conn.Open();
                        </span><span>int</span> rows =<span> cmd.ExecuteNonQuery();
                        </span><span>return</span><span> rows;
                    }
                    </span><span>catch</span><span> (System.Data.SqlClient.SqlException e)
                    {
                        conn.Close();
                        </span><span>throw</span><span> e;
                    }
                }
            }
        }

        </span><span>public</span> <span>object</span> GetSingle(<span>string</span><span> strSql)
        {
            </span><span>using</span> (OleDbConnection conn = <span>new</span><span> OleDbConnection(ConnectionString))
            {
                </span><span>using</span> (OleDbCommand cmd = <span>new</span><span> OleDbCommand(strSql, conn))
                {
                    </span><span>try</span><span>
                    {
                        conn.Open();
                        </span><span>object</span> obj =<span> cmd.ExecuteScalar();
                        </span><span>if</span> ((Object.Equals(obj, <span>null</span>)) ||<span> (Object.Equals(obj, System.DBNull.Value)))
                        {
                            </span><span>return</span> <span>null</span><span>;
                        }
                        </span><span>else</span><span>
                        {
                            </span><span>return</span><span> obj;
                        }
                    }
                    </span><span>catch</span><span> (System.Data.SqlClient.SqlException e)
                    {
                        conn.Close();
                        </span><span>throw</span><span> e;
                    }
                }
            }
        }</span>