If you are developing Shopping cart for your ASP.Net web application or any application that requires you to calculate shipping charges on the fly using the shipping carrier's web service then you definitely want to try our ShippingCalc.Net library. This sample demonstrates a very simple use of the library to show you how you can calculate shipping charges for USPS carrier.

Sub TestDomesticRateCalculator()
        Dim obGateway As WSGateway = 
            New WSGateway(CarrierType.USPS, "your unique id", String.Empty, "http://production.shippingapis.com/ShippingAPI.dll", False)
        Dim rateTxn As RateCalculationTransaction = obGateway.CreateDomesticRateCalculationTransaction()
        Dim obPackage As DomesticPackage = rateTxn.CreateNewDomesticPackage()
        obPackage.PackageID = "1"
        obPackage.OriginZip = "03033"
        obPackage.DestinationZip = "03063"
        obPackage.WeightInPound = 10
        obPackage.WeightInOunce = 5
        obPackage.PackageSizeType = PackageSizeType.Large
        obPackage.ContainerType = ContainerType.FlatRateBox
        obPackage.DeliveryServiceType = DeliveryServiceType.All
        obPackage.Machinable = True
        rateTxn.Packages.Add(obPackage)

        Dim obResp As GatewayResponse = obGateway.SubmitRateCalculationTransaction(rateTxn)
        If (obResp.StatusCode <> 0) Then
            Console.WriteLine("Gateway Error")
            If Not (obResp.GatewayError Is Nothing) Then
                Console.WriteLine(obResp.GatewayError.ErrorDescription)
                Return
            End If
        End If

        Console.WriteLine("Gateway Response")
        Dim obRespPackage As DomesticPackage
        For Each obRespPackage In rateTxn.Packages
            Console.WriteLine("***********START**************")
            Console.WriteLine("Package ID: {0}", obRespPackage.PackageID)
            Console.WriteLine(" Zone: {0}", obRespPackage.Zone)
            If Not (obRespPackage.PostageCollection Is Nothing) Then
                Dim obPostage As USPSDomesticPostage
                For Each obPostage In obRespPackage.PostageCollection
                    Console.WriteLine("\tService Type: {0} - Rate:{1}", obPostage.MailService, obPostage.MailRate)
                    Console.WriteLine("")
                Next obPostage
            End If
            Console.WriteLine("***********END****************")
            Console.WriteLine("")
        Next obRespPackage
    End Sub