Paypal IPN in asp.net VB

' ASP.NET VB

Imports System.Net
Imports System.IO

Partial Class vbIPNexample
Inherits System.Web.UI.Page

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
'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)

'Set values for the request back
req.Method = "POST"
req.ContentType = "application/x-www-form-urlencoded"
Dim Param() As Byte = Request.BinaryRead(HttpContext.Current.Request.ContentLength)
Dim strRequest As String = Encoding.ASCII.GetString(Param)
strRequest = strRequest + "&cmd=_notify-validate"
req.ContentLength = strRequest.Length

'for proxy
'Dim proxy As New WebProxy(New System.Uri("http://url:port#"))
'req.Proxy = proxy

'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 strResponse = "VERIFIED" Then
'check the payment_status is Completed
'check that txn_id has not been previously processed
'check that receiver_email is your Primary PayPal email
'check that payment_amount/payment_currency are correct
'process payment
ElseIf strResponse = "INVALID" Then
'log for manual investigation
Else
'Response wasn't VERIFIED or INVALID, log for manual investigation
End If
End Sub
End Class

Paypal IPN in asp.net c#

// ASP .NET C#

using System;
using System.IO;
using System.Text;
using System.Net;
using System.Web;

public partial class csIPNexample : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
//Post back to either sandbox or live
string strSandbox = "https://www.sandbox.paypal.com/cgi-bin/webscr";
string strLive = "https://www.paypal.com/cgi-bin/webscr";
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(strSandbox);

//Set values for the request back
req.Method = "POST";
req.ContentType = "application/x-www-form-urlencoded";
byte[] param = Request.BinaryRead(HttpContext.Current.Request.ContentLength);
string strRequest = Encoding.ASCII.GetString(param);
strRequest += "&cmd=_notify-validate";
req.ContentLength = strRequest.Length;

//for proxy
//WebProxy proxy = new WebProxy(new Uri("http://url:port#"));
//req.Proxy = proxy;

//Send the request to PayPal and get the response
StreamWriter streamOut = new StreamWriter(req.GetRequestStream(), System.Text.Encoding.ASCII);
streamOut.Write(strRequest);
streamOut.Close();
StreamReader streamIn = new StreamReader(req.GetResponse().GetResponseStream());
string strResponse = streamIn.ReadToEnd();
streamIn.Close();

if (strResponse == "VERIFIED")
{
//check the payment_status is Completed
//check that txn_id has not been previously processed
//check that receiver_email is your Primary PayPal email
//check that payment_amount/payment_currency are correct
//process payment
}
else if (strResponse == "INVALID")
{
//log for manual investigation
}
else
{
//log response/ipn data for manual investigation
}
}
}

ASP.NET AJAX UpdateProgress Control

In head Section

<script language="javascript" type="text/javascript">

   var prm = Sys.WebForms.PageRequestManager.getInstance();
   prm.add_initializeRequest(InitializeRequest);
   prm.add_endRequest(EndRequest);
   var postBackElement;
   function InitializeRequest(sender, args)
   {

      if (prm.get_isInAsyncPostBack())
         args.set_cancel(true);
      postBackElement = args.get_postBackElement();
      if (postBackElement.id == 'Button1')
         $get('UpdateProgress1').style.display = 'block';
   }
 
   function EndRequest(sender, args)
   {
       if (postBackElement.id == 'Button1')
          $get('UpdateProgress1').style.display = 'none';
   }

</script>

 In Body Section

<body>
    <form id="form1" runat="server">
    <div>
        &nbsp;
    </div>
        <asp:UpdatePanel ID="UpdatePanel1" runat="server">
            <ContentTemplate>
                <asp:Label ID="Label1" runat="server" Width="145px"></asp:Label>
            </ContentTemplate>
         <Triggers>
            <asp:AsyncPostBackTrigger ControlID="Button1" EventName="Click"/>
        </Triggers>
        </asp:UpdatePanel>
       <asp:UpdateProgress ID="UpdateProgress1" runat="server" DisplayAfter="0" AssociatedUpdatePanelID="UpdatePanel1">
            <ProgressTemplate>
                <script type="text/javascript">document.write("<div class='UpdateProgressBackground'></div>");</script>
                <center><div class="UpdateProgressContent">Loading...</div></center>
            </ProgressTemplate>
        </asp:UpdateProgress>

        <br />
        <br />
        <br />
        <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" />
    </form>
</body>