nullreferenceexception was unhandled by user code [Resolved]

Hi,
I Got an error: nullreferenceexception was unhandled by user code
while opening mysql connection through asp.net
for your information i am providing below the code from two files:

Code from connection.vb

Imports Microsoft.VisualBasic
Imports MySql.Data.MySqlClient

Public Class Conn
    Public adoconn As MySqlConnection
    Function dcon()
        adoconn = New MySqlConnection("server=localhost;database=TSdb;uid=root;pwd=123;AllowZeroDateTime=True;port=3306")
        Return Nothing
    End Function
End Class

Code from customermst.aspx.vb

Imports MySql.Data.MySqlClient
Partial Public Class cstmaster
    Inherits System.Web.UI.Page
    Dim con As MySqlConnection
    Dim cmd As MySqlCommand
    Dim rdr As MySqlDataReader
    Dim c1 As Conn = New Conn
    Dim str As String

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    End Sub

    Protected Sub sumbit_Click(ByVal sender As Object, ByVal e As EventArgs) Handles sumbit.Click
        con = c1.adoconn
        con.Open()
        str = "insert into tblcst(nm,addr,city,mailid) values('" & txtcstnm.Text & "','" & txtadd.Text & "','" & txtcity.Text & "','" & txtmailid.Text & "')"
        cmd = New MySqlCommand(str, con)
        rdr = cmd.ExecuteReader()
        rdr.Close()
        con.Close()
    End Sub
End Class

I am getting error (nullreferenceexception was unhandled by user code ) while passing the code:
con.Open()

Expecting your valuable reply in this regard to solve this issue.

[Resolved]