"未将对象引用设置到对象的实例"
在一个类中取web.config内的值的时候,提示 "未将对象引用设置到对象的实例 ",请问如何解决,谢谢.


web.config 中代码如下:

-------------------------------------
configuration xmlns= "http://schemas.microsoft.com/.NetConfiguration/v2.0 ">
<appSettings>
<!--注释：数据库连接字串-->
<add key= "Datebase " value= "contract.mdb " />
</appSettings>
--------------------------------------

在类中引用该值,代码如下:

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Imports Microsoft.VisualBasic
Imports System
Imports System.Web
Imports System.Configuration
Imports System.Data
Imports System.Data.OleDB

Namespace WJCclass

Public Class FindRecord

Public Function getMaxId() As Integer

Dim mDatabase As String
mDatabase = System.Configuration.ConfigurationManager.AppSettings( "Database ").ToString()
'Dim mDatabase As String = "contract.mdb "

Dim conDB As OleDbConnection
Dim selectDB As OleDbCommand
Dim MaxId As Integer

Dim mDBName As String = System.Web.HttpContext.Current.Server.MapPath(mDatabase)

conDB = New OleDbConnection( "PROVIDER=Microsoft.Jet.OLEDB.4.0; DATA Source= " + mDBName)
conDB.Open()
selectDB = New OleDbCommand( "select iif(max(BranchID) is null,0,max(BranchID)) from branch ", conDB)
MaxId = selectDB.ExecuteScalar()
If MaxId = 0 Then
MaxId = 1
Else
MaxId = MaxId + 1
End If

conDB.Close()
Return MaxId
End Function

End Class
End Namespace
------------------------------------


[解决办法]
放在同目录下了？
[解决办法]
System.Configuration.ConfigurationManager.AppSettings( "Database ").ToString()

AppSettings是属性不是方法

System.Configuration.ConfigurationManager.AppSettings[ "Database "].ToString()

不懂VB是不是也应该这样~
[解决办法]
那句出错啦？
[解决办法]
web.config
Datebase -> Database
[解决办法]
字打错了