ถามเกี่ยวกับการ Insert คับ(ASP.NET,VB) คือ ผมลองทำดู แต่ไม่รู้ทำไม มัน Error คับ ช่วยดูให้ที คับบบบ

Page.Culture = "en-US"
            Dim StrConn2 As String = WebConfigurationManager.ConnectionStrings("conn").ConnectionString
            Dim conn2 As New SqlConnection(StrConn2)
            conn2.Open()
            Dim cmd As String
            cmd = "insert into order (id_drug , quantity_sale , discount , date_sale)"
            cmd &= " values ('" & id_drug1 & "',"
            cmd &= "'" & num.Text & "',"
            cmd &= "'" & discount.Text & "',"
            cmd &= "'" & Now.ToString & "')"
            Dim com As New SqlCommand(cmd, conn2)
            com.ExecuteNonQuery()
            conn2.Close()