Error: Variable 'conn' hides a variable in an enclosing block.

Member 8761667

Hello With the error above, I understand that Visual Studio is telling me that 'conn' needs to be renamed. This is my code:

Protected Sub btnPassSend_Click(sender As Object, e As EventArgs) Handles btnPassSend.Click

    Dim cmd As OleDbCommand
    Dim dt As DataTable
    **Dim conn As New OleDbConnection
    'Dim conn1 As New OleDbConnection**        Dim adp As OleDbDataAdapter

    Using conn As OleDbConnection = New OleDbConnection(System.Configuration.ConfigurationManager.ConnectionStrings("students").ConnectionString)

        If conn.State = ConnectionState.Closed Then
            conn.Open()

        End If

        Dim SQL As String = "SELECT strEmail FROM university (strEmail) WHERE (strEmail=@strEmail)"
        cmd.Parameters.AddWithValue("@strEmail", UserEmail.Text)
        cmd.ExecuteNonQuery()
        conn.Close()

    End Using

    Try
        'In OleDbDataAdapter, execute the SQL and check that the user's email corresponds to that in the MDB

        adp = New OleDbDataAdapter("SELECT strEmail FROM university WHERE strEmail=@strEmail", conn)

        'Pass email parameter named email from the value of Mail.Sent.Text

        cmd.Parameters.AddWithValue("@strEmail", UserEmail)

        dt = New DataTable()

        adp.Fill(dt)

        If dt.Rows.Count = 0 Then

            ErrorMail.Text = "Please enter a valid email address"

            Return

        Else

            Dim code As String

            code = Guid.NewGuid().ToString()

            ' and am updating the code column of the table with this value. i mean inside the code column i'll store the value

            ' that was inside the code variable

            cmd = New OleDbCommand("UPDATE university SET code=@code WHERE strEmail=@strEmail", conn)

            cmd.Parameters.AddWithValue("@code", code)

            cmd.Parameters.AddWithValue("@email", UserEmail.Text)

            ' here i am difinning a StringBuilder class named sbody

            Dim sbody As New StringBuilder()

            'Send image as logo with the path http://whatever.com

            sbody.Append("[![](http://mySite.com/my_image.jpg/)](http://whatever.com)

")

            'Send link to user's email with email and code using querystring

            sbody.Append("[](http://usingasp.net/reset_pwd.aspx?e</x-turndown)

Lost User

When you create a variable in a using block you should not have it dimensioned outside. Just remove the line:

Dim conn As New OleDbConnection

Member 8761667

Hello Richard Many thanks for your reply. When I do that, as follows:

Dim cmd As OleDbCommand
Dim dt As DataTable
'Dim conn As New OleDbConnection
'Dim conn1 As New OleDbConnection
Dim adp As OleDbDataAdapter

I just get: Error 1:'conn' is not declared. It may be inaccessible due to its protection level. Thanks again for your help.

Richard Andrew x64

One thing you're doing wrong is that you have conn declared inside a Using block, but the Using block ends before your Try block. When the Using block ends, it disposes the connection, so you cannot go on to use the connection inside the Try block.

The difficult we do right away... ...the impossible takes slightly longer.

Member 8761667

I have separated 'Using' from 'Try' now - thank you.

Protected Sub btnPassSend_Click(sender As Object, e As EventArgs) Handles btnPassSend.Click

conn = New OleDbConnection()

conn = New OleDbConnection(System.Configuration.ConfigurationManager.ConnectionStrings("students").ConnectionString)

conn.Open()

If conn.State = ConnectionState.Closed Then

conn.Open()

End If

Using conn As OleDbConnection = New OleDbConnection(System.Configuration.ConfigurationManager.ConnectionStrings("students").ConnectionString)

adp = New OleDbDataAdapter("SELECT strEmail FROM university WHERE strEmail=@strEmail", conn)

cmd.Parameters.AddWithValue("@strEmail", Request.QueryString("UserEmail").ToString())

cmd.ExecuteNonQuery()

conn.Close()

End Using

Dim sbody As New StringBuilder()

sbody.Append("[")

Try

Dim SMTPserver As New System.Net.Mail.SmtpClient("smtp.mail.server", 25)

Dim SMTPMail As New System.Net.Mail.MailMessage("LostPwd", "strEmail")

Dim mailAuthenticaion As New System.Net.NetworkCredential("info@mySite.com ", "SMTP server password")

SMTPserver.EnableSsl = True
SMTPserver.Credentials = mailAuthenticaion

SMTPMail.To.Add("LostPwd.Text".ToString())
SMTPMail.CC.Add("")
SMTPMail.Bcc.Add("Webmaster@mySite.com")
SMTPMail.From = New MailAddress("info@mySite.net")
SMTPMail.Subject = "Please reset your password"
SMTPMail.Body = sbody.ToString()
SMTPMail.IsBodyHtml = True
SMTPserver.Send(SMTPMail)

cmd.ExecuteNonQuery()

cmd.Dispose()

conn.Close()

LostPwd.Text = "Password reset link sent"

Catch ex As Exception

LostPwd.Text = "" 'Error message here

Finally

conn.Close() 'close the database

End Try

End Sub](http://usingasp.net/reset_pwd.aspx?email=")

Richard Andrew x64

Now you're instantiating conn twice! Once before the Using block, and then again inside the Using block. And you're still ending the Using block before the Try block, so the connection is being closed and disposed before you get to the heart of the code.

The difficult we do right away... ...the impossible takes slightly longer.

Member 8761667

You would think that would generate an error, wouldn't you? I have now removed

If conn.State = ConnectionState.Closed Then
conn.Open()

        End If

from inside 'Using' and I have moved 'End Using' right to the bottom

Finally

            conn.Close() 'close the database

        End Try

    End Using

End Sub

End Class

so it encompasses both the database part of the code and the SMTP part. I had better read up on 'Using' - thanks for pointing it out.

Richard Andrew x64

Glad I could help. :)

The difficult we do right away... ...the impossible takes slightly longer.