string connection="Provider=Microsoft.Jet.OLEDB.4.0;Server=MyMDB.mdb"; 
string sqlConnection="SECLET * FROM ***DB"; 

System.Data.OleDb.OleDbConnection oleDbConnection=new System.Data.OleDb.OleDbConnection(connection); 

DataSet dataset=DataSet(); 

System.Data.OleDb.OleDataAdapter oleDataAdapter=new System.Data.OleDb.OleDataAdapter(sqlConnection,oleDbConnection); 

oleDbConnection.Open(); 
oleDataAdapter.Fill(dataSet,"***DB"); 
dataGridView.DataSource=dataSet.Tables["***DB"];

------解决方案--------------------
Public conStr As String = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=" & System.Web.HttpContext.Current.Server.MapPath("数据库路经")
dim intcount as int=0
  dim  str1 as string  = "select   count(*)   as   ID   from   数据库表名"
Dim conn As New OleDbConnection(conStr)
       Dim cmd As New OleDbCommand(str1, conn)
       conn.Open()
       Dim dr As OleDbDataReader = cmd.ExecuteReader
       If dr.Read() Then
           intcount = dr("ID")
       Else
           intcount = 0
       End If
       dr.Close()
       conn.Close()
       conn.Dispose()

------解决方案--------------------
C# code
//连接的access
string connection="Provider=Microsoft.Jet.OLEDB.4.0;Server=MyMDB.mdb"; 
//查询的access里面的表
string sqlConnection="SECLET * FROM ***DB"; 
//连接
System.Data.OleDb.OleDbConnection oleDbConnection=new System.Data.OleDb.OleDbConnection(connection); 

DataSet dataset=DataSet(); 

System.Data.OleDb.OleDataAdapter oleDataAdapter=new System.Data.OleDb.OleDataAdapter(sqlConnection,oleDbConnection); 
//打开连接
oleDbConnection.Open(); 
//填充数据到DataSet
oleDataAdapter.Fill(dataSet,"***DB"); 
//在dataGridView显示出查询出来的数据
dataGridView.DataSource=dataSet.Tables["***DB"];

------解决方案--------------------
web.config
 <connectionStrings>
   <add name="DBPath" connectionString="~/#taohaodb#/#xinfor#.mdb"/>
   <!--数据库路径，前面的~必须保留-->
 </connectionStrings>
连接类
string connStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source="+ System.Web.HttpContext.Current.Server.MapPath(ConfigurationManager.ConnectionStrings["DbPath"].ToString())