Get Paypal Express cart结账前的价格

Question

我正在使用PayPal快速结帐，并试图在用户决定结帐时获取购物车中的总价值。我的运费将以总价为基础，虽然我的PayPal帐户设置中填写了运费计算，但运费在结帐屏幕上并未显示。如何在结帐时获取总购物车价格，以便我可以添加运费？到目前为止，我所拥有的只是用户签出后的价值，他们会被退回到我的网站，但在这一点上，加入运费已经太迟了。

Dim authToken As String = "sdf5414FdsfDFS5eEF52s336DFLLJUhhbuzek64" 
    Dim txToken As String = Request.QueryString("tx") 
    txToken = "4GGSES84eEWSS" 
    Dim strRequest As String = "cmd=_notify-synch&tx=" & txToken & "&at=" & authToken 

    'Dim Payerinfo As New PayerInfo 
    'Dim trans As New Transaction 
    'Dim tra As New PayPal.PayPalAPIInterfaceService.Model.GetTransactionDetailsReq 




    'post back to either sandbox or live 
    Dim strSandbox As String = "https://www.sandbox.paypal.com/cgi-bin/webscr" 
    Dim strLive As String = "https://www.paypal.com/cgi-bin/webscr" 
    Dim req As HttpWebRequest = CType(WebRequest.Create(strSandbox), HttpWebRequest) 
    'req.Headers = valHeader 
    'Set values for the request back 
    req.Method = "POST" 
    req.ContentType = "application/x-www-form-urlencoded" 
    req.ContentLength = strRequest.Length 

    'Send the request to PayPal and get the response 
    Dim streamOut As StreamWriter = New StreamWriter(req.GetRequestStream(), Encoding.ASCII) 
    streamOut.Write(strRequest) 
    streamOut.Close() 
    Dim streamIn As StreamReader = New StreamReader(req.GetResponse().GetResponseStream()) 
    Dim strResponse As String = streamIn.ReadToEnd() 
    streamIn.Close() 

    If Not String.IsNullOrEmpty(strResponse) Then 

     Dim results As New Dictionary(Of String, String) 
     Dim reader As New StringReader(strResponse) 
     Dim line As String = reader.ReadLine() 
     If line = "SUCCESS" Then 
      'FormView1.Visible = False 
      While True 
       Dim aLine As String 
       aLine = reader.ReadLine 
       If aLine IsNot Nothing Then 
        Dim strArr() As String 
        strArr = aLine.Split("=") 
        results.Add(strArr(0), strArr(1)) 
       Else 
        Exit While 
       End If 
      End While 

      ' Displays all the keys for results, helps to see what the keys are named for writing to text file 

      For Each kvp As KeyValuePair(Of String, String) In results 
       Dim v1 As String = kvp.Key 
       Dim v2 As String = kvp.Value 
       Response.Write(v1.ToString _ 
         + ": " + v2 + "<br /> ") 
      Next 

     End If 

我也一直在试图定义一个session变量，并加入到它的每一个被点击的添加到购物车按钮的时间，但我看到这个问题，因为我不知道该项目将有多长留贝宝手推车，如果会话变量会话耗尽时间并被清除，他们将收到免费送货，因为运送金额清除。他们有什么方法可以做到这一点？

Protected Sub AddToCartBtn_Click(sender As Object, e As EventArgs) 
Session("CartAmount")  

Dim itemNumber As String = str2 
    Dim itemAmount As String = price 
    Dim currencyCode As String = "USD" 
    Dim addItem As Integer = 1 

    Dim ppHref As StringBuilder = New StringBuilder() 
    ppHref.Append("https://www.sandbox.paypal.com/cgi-bin/webscr?cmd=_cart") 
    ppHref.Append("&business=" + business) 
    ppHref.Append("&item_name=" + itemName) 
    ppHref.Append("&item_number=" + itemNumber) 
    ppHref.Append("&amount=" + itemAmount) 
    ppHref.Append("&currency_code=" + currencyCode) 
Session("CartAmount") = (cartTotal + Session("CartAmount")) 
End Sub 

Answer 1

您可以从以下网址参考提供的变量传递的购物车价值 https://developer.paypal.com/docs/classic/paypal-payments-standard/integration-guide/Appx_websitestandard_htmlvariables/#id08A6HF080O3