SQL Server 2005 - Problem

I wrote a subroutine in VB in the server on the click event of a button which connect to a database and checks if any data is there. But it gives an error as

[NullReferenceException: Object reference not set to an instance of an object.]
teachersvoice.Admin.Button1_Click(Object sender, EventArgs e) in D:\teachersvoice\teachersvoice\Admin.aspx.vb:18
System.Web.UI.WebControls.Button.OnClick(EventArgs e) +111
System.Web.UI.WebControls.Button.RaisePostBackEven t(String eventArgument) +110
System.Web.UI.WebControls.Button.System.Web.UI.IPo stBackEventHandler.RaisePostBackEvent(String eventArgument) +10
System.Web.UI.Page.RaisePostBackEvent(IPostBackEve ntHandler sourceControl, String eventArgument) +13
System.Web.UI.Page.RaisePostBackEvent(NameValueCol lection postData) +36
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565


The code is

Imports Microsoft.VisualBasic
Imports System.Collections.Generic
Imports System.Data
Imports System.Data.SqlClient


Partial Public Class Admin
Inherits System.Web.UI.Page
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click
Dim p As Integer
Dim tday As Date
tday = Today()
'Dim conn As SqlConnection
'Dim cmd As SqlCommand
Dim cmdstring As String = " select * from hitno where date = '" & tday & "'"
Dim conn = New SqlConnection("Provider = SQLOLEDB;Data Source = localhost; Initial Catalog = teachersvoice; UserId = sarkar; Password = chandra;")
Dim cmd = New SqlCommand(cmdstring, conn)
conn.Open()
p = cmd.ExecuteNonQuery()
MsgBox(p)
End Sub

End Class

There's nothing wrong with your sql statement. Something is wrong with your vb code. "Object reference not set to an instance of an object" is a very common error which means simply that you are reference an object which has been declared, but has not yet been instantiated. Sometimes you get this from doing things in the wrong order. I don't have Visual Studio installed on this laptop I'm using right now, so I can't try your code and tell you the exact location of your problem.