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POAvoid NullReferenceException
 

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    <p>I'm fairly new to .NET programming. I am trying to check if there are settings in a database table and if not, create some default settings. The problem is that when there are no settings I need to make two calls with the datareader and it keeps giving me problems.</p> <p>I originally was only using one datareader but made two to attempt resolving my issue, didn't work.<br> Then I tried closing the datareader and I get errors because it returned a nullreference. </p> <p>If I try to close it I get an issue, if I don't close it the next one gives me an error saying there is already an open datareader on this connection that needs to be closed. Can anyone tell me how I can refactor my code to get this to work (preferably with one datareader)?</p> <p>I also tried putting the reader.close() in another set of try catch, while that enables me to catch the error, it still doesn't close the datareader so I am at a loss.</p> <pre><code>Private Sub Get_Initial_Settings() Dim reader1 As MySqlDataReader = Nothing, reader2 As MySqlDataReader = Nothing Dim cmd As New MySqlCommand("SELECT depot, size, roc_family, wil_family, ast_family, met_family, ric_family, view FROM vb_dashboard.user_preferences WHERE " &amp; GetUserName() &amp; "", conn) Dim hasSettings As Boolean 'Get Personal Settings or initiate them if necessary Try reader1 = cmd.ExecuteReader hasSettings = True MessageBox.Show("Your user settings show you have a selected depot of " &amp; reader1(0).ToString) Catch ex As Exception 'No settings exist, set some up MessageBox.Show("You have no settings for this program yet") hasSettings = False Finally reader1.Close() End Try 'User has no preferences, Create some 'First, create a list of depots to select from and add it to a combobox If (hasSettings = False) Then Try cmd.CommandText = "SELECT depot FROM vb_dashboard.depots ORDER BY depot" reader2 = cmd.ExecuteReader While (reader2.Read) dlgSelectDepot.cbDepotSelect.Items.Add(reader2.GetString(0)) End While 'Now show the dialog box to initiate a depot setting Me.Hide() dlgSelectDepot.Show() Me.Show() If (dlgSelectDepot.DialogResult = Windows.Forms.DialogResult.Cancel) Then Me.Close() End If cmd.CommandText = "INSERT INTO vb_database.user_preferences SET user='" &amp; GetUserName.ToUpper &amp; "', depot='Rochester'" cmd.ExecuteNonQuery() Catch ex As Exception MessageBox.Show("An error has occurred: " &amp; ex.Message) Finally reader2.Close() End Try End If End Sub </code></pre>
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