ExecuteScalar IB VB.NET

CLASS  
 Dim con As SqlConnection = New SqlConnection()
    Dim com As SqlCommand = New SqlCommand()
    Dim da As SqlDataAdapter = New SqlDataAdapter()
    Dim constr As String = "Data Source=SERVER NAME \SQLEXPRESS;Initial Catalog=DBNAME;Integrated Security=True"

  Public Function SelectScalar(ByVal str As String) As String
        Dim s1 As String
        If con.State = ConnectionState.Closed Then
            con.ConnectionString = constr
            con.Open()
        End If
        com.CommandText = str
        com.Connection = con
        da.SelectCommand = com
        s1 = Convert.ToString(com.ExecuteScalar())
        con.Close()
        Return s1
    End Function
  Dim c1 As clsConnection = New clsConnection()//OBJECT OF CLASS
PAGE
Dim check As String = "select count(equip_id) from TBLNAEM where equip_id='" & ddlEquipment.SelectedValue & "' "
        Dim i As Integer = (Convert.ToInt32(c1.SelectScalar(check)))