Re: New to VB.NET...HELP REQUIRED IMMEDIATELY

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From: Scott M. (s-mar_at_nospam.nospam)
Date: 01/28/05 

Date: Thu, 27 Jan 2005 19:51:17 -0500

I don't see him using one connection for 2 different commands. I see him
calling ExecuteReader on the same command twice. There is only one command
object in his code.

"W.G. Ryan eMVP" <WilliamRyan@gmail.com> wrote in message
news:OnGYw1KBFHA.3576@TK2MSFTNGP11.phx.gbl...
> Scott already answered the crux of your problem - you are using the same
> connection for two different commands which you can't do until ADO.NET 2.0
>
> But since your first execution is MAX() - then you should probably opt for
> ExecuteScalar instead of Reader. If nothing else it will save you a few
> lines of code and make your intent a little clearer.
>
> Also, you should consider using a Finally Block and closing your
> connection
> in the finally - that's the only way youy can make sure it will get
> closed.
>
> And as always - I have to include my obligatory rant against catching
> system.Exception here. Since your not doing anything with your exception
> other than writing it out - you probably ought to catch a OleDbException
> for
> the connection.Open and the Execute statements - if you got a
> StackOverflow
> or something else there - well you may want to respond differently. But
> that's another story.
>
> --
> W.G. Ryan, MVP
>
> www.tibasolutions.com | www.devbuzz.com | www.knowdotnet.com
> "santosh singh via DotNetMonster.com" <forum@DotNetMonster.com> wrote in
> message news:09d9cc428c6e41a4b297c987ab109eac@DotNetMonster.com...
>> Hi,
>> I'm new to VB.NET..I'm developing a login page...im getting this error..
>>
>> System.InvalidOperationException: ExecuteReader requires an open and
> available Connection. The connection's current state is Open, Fetching. at
> System.Data.OleDb.OleDbCommand.ValidateConnectionAndTransaction(String
> method, Int32& localState) at
> System.Data.OleDb.OleDbCommand.ExecuteReaderInternal(CommandBehavior
> behavior, String method) at
> System.Data.OleDb.OleDbCommand.ExecuteReader(CommandBehavior behavior) at
> System.Data.OleDb.OleDbCommand.ExecuteReader() at
> bt.index.Page_Load(Object
> sender, EventArgs e) in d:\inetpub\wwwroot\bt\index.aspx.vb:line 56
>>
>>
>> The code in .aspx.vb page is
>>
>>
>> Private Sub Page_Load(ByVal sender As System.Object, ByVal e As
> System.EventArgs) Handles MyBase.Load
>> 'Put user code to initialize the page here
>> If Not IsPostBack Then
>> Try
>>
>>
>>
>> Dim MyConn As OleDbConnection = New
> OleDbConnection(ConfigurationSettings.AppSettings("strConn"))
>> Dim strVisitor As String
>> Dim visitorCmd As OleDbCommand
>> Dim vRdr As OleDbDataReader
>> strVisitor = "select max(v_id) from visitor"
>> visitorCmd = New OleDbCommand(strVisitor, MyConn)
>> MyConn.Open()
>> Dim old_visitor As Integer
>> Dim new_visitor As Integer
>>
>> vRdr = visitorCmd.ExecuteReader()
>> While vRdr.Read()
>> If Not IsDBNull(visitorCmd.ExecuteReader()) Then
>> old_visitor = vRdr.Item(0)
>> End If
>> End While
>>
>> new_visitor = old_visitor + 1
>> lblvisitor.Text = new_visitor
>> MyConn.Close()
>>
>> Catch ex As Exception
>> Response.Write(ex)
>> End Try
>>
>> End If
>> End Sub
>>
>>
>>
>> Your help will be much appreciated
>>
>> --
>> Message posted via http://www.dotnetmonster.com
>
>

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