数据库中的数据到vb.net中的label.text

Question

我希望使用以下代码将数据库中的信息显示为标签。但我总是得到一个＆＃34;对象引用未设置为对象的实例＆＃34;错误。我的代码是否正确？或者你可以用更好的代码帮助我吗？

Imports MySql.Data.MySqlClient

Public Class dbtolabel
    Dim Mysqlconn As MySqlConnection
    Dim Command As MySqlCommand

    Private Sub conn()
        Mysqlconn = New MySqlConnection
        Mysqlconn.ConnectionString = "server = localhost; userid = root; password = root; database = db_payroll"

    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        conn()

        Try
            Dim Reader As MySqlDataReader

            Mysqlconn.Open()
            Command.Connection = Mysqlconn

            Command.CommandText = "select lastname from dbsample.tblemployees where barcode like '" & TextBox1.Text & "'"
            Reader = Command.ExecuteReader()

            If Reader.Read() Then
                Label2.Text = Reader.Item(2).ToString

            End If

            Reader.Close()
            Mysqlconn.Close()
        Catch ex As Exception
            MsgBox(ex.Message)

        End Try
    End Sub
End Class`