Question

asp.net2.0中用VB.NET如何引用在web.config中定义了连接字符串

asp.net2.0中用VB.NET如何引用在web.config中定义了连接字符串
在web.config中定义的连接字符串如下：
请问如何引用？
如：Dim conn As New SqlConnection(？？？)
---------------------------------------------------------------------------------------------------------
<add name="student" connectionString="Provider=Microsoft.Jet.OLEDB.4.0;Data Source="C:\Users\peng\Documents\Visual Studio 2008\WebSites\WebSite7\App_Data\student.mdb";Persist Security Info=True;Jet OLEDB:Database Password=198404"
providerName="System.Data.OleDb" />

Answer 1

Dim rootWebConfig As System.Configuration.Configuration
rootWebConfig = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration("/MyWebSiteRoot")
Dim connString As System.Configuration.ConnectionStringSettings
If (0 < rootWebConfig.ConnectionStrings.ConnectionStrings.Count) Then
connString = rootWebConfig.ConnectionStrings.ConnectionStrings("NorthwindConnectionString")
If Not (Nothing = connString.ConnectionString) Then
Console.WriteLine("Northwind connection string = {0}", connString.ConnectionString)
Else
Console.WriteLine("No Northwind connection string")
End If
End If

追问

你好，多谢回复，但无法引用WEB.CONFIG中的连接字符串，请问高手Dim conn As New SqlConnection(？？？)中的三个问题该填写什么内容？非常感谢

追答

Oh,Sorry，之前可能是我没注意你贴的问题，您要连接的是 OLEDB ，可我贴的是连接SQL的。不好意思。

先说下 SqlConnection的事， SqlConnection没有三个参数的构造器吧，不知你写的New SqlConnection(? ? ?)要传三个参数? SqlConnection只有SqlConnection ()和SqlConnection (String)。

这里再 贴下 连接 OLEDB(感觉你这里应该是Access数据库)，其实道理都一样，.NET 提供了统一的API。
Dim connetionString As String
Dim cnn As OleDbConnection
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=yourdatabasename.mdb;"
cnn = New OleDbConnection(connetionString)
Try
cnn.Open()
cnn.Close()
Catch ex As Exception
End Try
在之前还要Imports System.Data.OleDb;

Answer 2

Dim DB_ConnStr As String = ConfigurationSettings.AppSettings("student")

SqlConnection Conn = New SqlConnection(DB_ConnStr)