自定义数据库链接类(Access)是链接Access数据库时使用的类。
补足：Application.StartupPath.ToString是指定生成.EXE文件的路径，把数据库和执行文件存放到一起时，不管安装后在什么路径都无需特定指定。
Imports System.Data.OleDb
#Region "全局变量"
Private mTimeout As Integer
Private mDbConn As OleDbConnection
Private mSqlConn As OleDbCommand 'SQL执行
Private sTblNm As String '存放数据的表名
Private mbOpen As Boolean 'DB链接判断用
Private mDbReader As OleDbDataReader
Private mDbTrans As OleDbTransaction
Private mbTran As Boolean = False 'Transaction开始判断用
Private sSqlStr As String 'SQL文
Private mDbResult As DB_RESULT 'EXECUTE方法的处理结果
Private mDbConnStr As String = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=" & Application.StartupPath.ToString & _
&nbs
已知有一个XML文件（bookstore.xml）如下：
<?xml version="1.0" encoding="gb2312"?>
<bookstore>
<book genre="fantasy" ISBN="2-3631-4">
<title>Oberon's Legacy</title>
<author>Corets, Eva</author>
<price>5.95</price>
</book>
< ......
