C# HDFC Payment Gateway ( UMI Method ) Implementation

1. Payment Request Page
   
   protected void Page_Load(object sender, EventArgs e)
   {
   
   #region UMI Method Implementation
   
   string TranTrackid = string.Empty;
   string TranAmount = string.Empty;
   
   TranTrackid = YOUR TRANSACTION ID;
   TranAmount = PAYMENT AMOUNT;
   
   string ReqTranportalId = string.Empty;
   string ReqTranportalPassword = string.Empty;
   ReqTranportalId = "id=" + TRANSPORTAL ID PROVIDED BY BANK + "&";
   ReqTranportalPassword = "password=" + TRANSPORTAL PASSWORD PROVIDED BY BANK + "&";
   
   string ReqAction = "action=" + "1" + "&";
   string ReqLangid = "langid=" + "USA" + "&";
   string ReqCurrency = "currencycode=" + "356" + "&";
   //356 FOR INR
   string ReqAmount = "amt=" + TranAmount + "&";
   
   int pos = Request.Url.AbsoluteUri.LastIndexOf('/');
   string strURL = Request.Url.AbsoluteUri.Substring(0, pos + 1) + "PaymentResponseHDFC.aspx";
   //RESPONSE PAGE URL
   string strErrorURL = Request.Url.AbsoluteUri.Substring(0, pos + 1) + "PaymentError.aspx";
   //ERROR PAGE URL
   string ReqResponseUrl = "responseURL=" + strURL + "&";
   string ReqErrorUrl = "errorURL=" + strErrorURL + "&";
   
   string ReqTrackId = "trackid=" + TranTrackid + "&";
   
   string HDFCPayURL = string.Empty;
   HDFCPayURL = SECUREPG; //SECUREPGTEST for UAT and SECUREPG for PRODUCTION
   
   string ReqUdf1 = string.Empty;
   string ReqUdf2 = string.Empty;
   string ReqUdf3 = string.Empty;
   string ReqUdf4 = string.Empty;
   string ReqUdf5 = string.Empty;
   
   ReqUdf1 = "udf1=" + FirstName + "&";            // UDF1 values                                                               
   ReqUdf2 = "udf2=" + PersonalEmailID + "&";        // UDF2 values                                                                   
   ReqUdf3 = "udf3=" + MobileNumber + "&";             // UDF3 values
   ReqUdf4 = "udf4=" + City +"&";                 // UDF4 values       
   ReqUdf5 = "udf5=" + UserIdentifier + "&";        // UDF5 values 
   
   try
   {
       string TranResponse = "";//Declaration of variable
       string TranRequest = ReqTranportalId + ReqTranportalPassword + ReqAction + ReqLangid + ReqCurrency + ReqAmount + ReqResponseUrl + ReqErrorUrl + ReqTrackId + ReqUdf1 + ReqUdf2 + ReqUdf3 + ReqUdf4 + ReqUdf5;
       string TranUrl = "https://" + HDFCPayURL + ".fssnet.co.in/pgway/servlet/PaymentInitHTTPServlet";
       System.IO.StreamWriter myWriter = null;
   
       // it will open a http connection with provided url
       System.Net.HttpWebRequest objRequest = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(TranUrl);//send data using objxmlhttp object
       objRequest.Method = "POST";
       objRequest.ContentLength = TranRequest.Length;
       objRequest.ContentType = "application/x-www-form-urlencoded";//to set content type
       myWriter = new System.IO.StreamWriter(objRequest.GetRequestStream());
       myWriter.Write(TranRequest);//send data
       myWriter.Close();//closed the myWriter object
   
       System.Net.HttpWebResponse objResponse = (System.Net.HttpWebResponse)objRequest.GetResponse();
       //receive the responce from objxmlhttp object
       using (System.IO.StreamReader sr = new System.IO.StreamReader(objResponse.GetResponseStream()))
       {
       TranResponse = sr.ReadToEnd();
   
       string[] ErrorCheck = GetStringInBetween(TranResponse, "!", "!-", false, false);//This line will find Error Keyword in TranResponse   
   
       if (ErrorCheck[0] != "ERROR")//This block will check for Error in TranResponce
       {
           // Merchant MUST map (update) the Payment ID received with the merchant Track Id in his database at this place.
           string payid = TranResponse.Substring(0, TranResponse.IndexOf(":http"));
           string payURL = TranResponse.Substring(TranResponse.IndexOf("http"));
           // here redirecting the customer browser from ME site to Payment Gateway Page with the Payment ID
   
           //UPDATE THE payid(PAYMENT ID) IN DB
           //
           //CODE FOR UPDATE PAYMENT ID
           //
   
           //REDIRECT ON payURL(PAYMENT GATEWAY URL)
           string TranRedirect = payURL + "?PaymentID=" + payid;
           Response.Redirect(TranRedirect);
       }
       else
       {
           string TranErrorUrl = strErrorURL + "?Message=Transaction Failed&ResTrackId=" + TranTrackid + "&ResAmount=" + TranAmount + "&ResError=" + TranResponse;
      
           //REDIRECT TO ERROR PAGE   
           Response.Redirect(TranErrorUrl);
       }
   
       }
   }
   catch (Exception ex)// any excpetion occurred for above code exception throws here
   {
       //REDIRECT ON ERROR PAGE IN CASE OF ERROR
   }
   
   }
   
   #endregion
   
   }
   
   public static string[] GetStringInBetween(string strSource, string strBegin, string strEnd, bool includeBegin, bool includeEnd)
       {
           string[] result = { "", "" };
           int iIndexOfBegin = strSource.IndexOf(strBegin);
           if (iIndexOfBegin != -1)
           {
               // include the Begin string if desired
   
               if (includeBegin)
               {
                   iIndexOfBegin -= strBegin.Length;
               }
               strSource = strSource.Substring(iIndexOfBegin + strBegin.Length);
               int iEnd = strSource.IndexOf(strEnd);
               if (iEnd != -1)
               {  // include the End string if desired
                   if (includeEnd)
                   { iEnd += strEnd.Length; }
                   result[0] = strSource.Substring(0, iEnd);
                   // advance beyond this segment
                   if (iEnd + strEnd.Length < strSource.Length)
                   { result[1] = strSource.Substring(iEnd + strEnd.Length); }
               }
           }
           else
           // stay where we are
           { result[1] = strSource; }
           return result;
       }//String function end
   
2. Payment Response Page
   
   
   protected void Page_Load(object sender, EventArgs e)
   {
   
       #region UMI Method Implementation
   
       string strResponceIP, TranInqResponse, ResPaymentId, ResResult, ResErrorText, ResPosdate, ResTranId, ResAuth, ResAVR, ResAmount, ResErrorNo, ResTrackID, ResRef, Resudf1, Resudf2, Resudf3, Resudf4, Resudf5, EMI;
   
       strResponceIP = HttpContext.Current.Request.UserHostAddress;
       int pos = Request.Url.AbsoluteUri.LastIndexOf('/');
   
       VALIDATE THE IP ADDRESS
   
   
       if ( ( (HOSTED ON PRODUCTION) && strResponceIP != "221.134.101.187" && strResponceIP != "221.134.101.175" && strResponceIP != "221.134.101.166" && strResponceIP.Trim() != "10.1.40.2")
           || ( (HOSTED ON UAT) && strResponceIP != "221.134.101.174" && strResponceIP != "221.134.101.169" && strResponceIP.Trim() != "10.1.40.2"))
       {
           //REDIRECT TO ERROR PAGE IF IP DOES NOT MATCH
       }
       else
       {
           // IP MATCHED
          
           ResErrorText = Request["ErrorText"];        //Error Text/message
           ResPaymentId = Request["paymentid"];        //Payment Id
           ResTrackID = Request["trackid"];            //Merchant Track ID
           ResErrorNo = Request["Error"];            //Error Number
   
           //To collect transaction result
           ResResult = Request["result"];            //Transaction Result
           ResPosdate = Request["postdate"];            //Postdate
           //To collect Payment Gateway Transaction ID, this value will be used in dual verification request
           ResTranId = Request["tranid"];            //Transaction ID
           ResAuth = Request["auth"];                //Auth Code       
           ResAVR = Request["avr"];                //TRANSACTION avr                   
           ResRef = Request["ref"];                //Reference Number also called Seq Number
           //To collect amount from response
           ResAmount = Request["amt"];                //Transaction Amount
   
           Resudf1 = Request["udf1"];                //UDF1
           Resudf2 = Request["udf2"];                //UDF2
           Resudf3 = Request["udf3"];                //UDF3
           Resudf4 = Request["udf4"];                //UDF4
           Resudf5 = Request["udf5"];                //UDF5
   
           try
           {
           // LOG THE RESPONSE FIRST
           string strRemarks = "Paymentid: " + ResPaymentId + " Result: " + ResResult + " ResErrorText:" + ResErrorText + " ResErrorNo:" + ResErrorNo + " ResAVR:" + ResAVR + " ResAmount:" + ResAmount + " ResRef:" + ResRef + " Postdate: " + ResPosdate + " PGTransactionID: " + ResTranId + " TransactionID: " + ResTrackID + " auth: " + ResAuth + " Resudf1: " + Resudf1 + " Resudf1: " + Resudf2 + " Resudf3: " + Resudf3 + " Resudf4: " + Resudf4 + " Resudf5: " + Resudf5;
           GlbFunctions.LogEvent(Page, "3.Response Page Param values: " + strRemarks + " Response Time: " + DateTime.Now.ToString("dd/MM/yyyy hh:mm:ss"), "S");
           }
           catch (Exception ex)
           {
           GlbFunctions.LogError("Payment Verify - Logging result", "Message: " + ex.Message + " StackTrace: " + ex.StackTrace, "WEBAPPLN_UI_TRANSACTIONS_PaymentResponseHDFC", "Page_Load", "UI", "-1");
           }
   
           if (ResErrorNo == null)
           {   
           //check result is captured or approved i.e. successful
           if (ResResult == "CAPTURED" || ResResult == "APPROVED")//If resulr is CAPTURED or APPROVED then below Code is execute for dual inquiry
           {
               //Validate parameters   
               if (ResPaymentId == null || ResTrackID == null || ResTranId == null || ResAuth == null || ResRef == null || ResAmount == null)
               {
               // REDIRECT TO ERROR PAGE IF REQUIRED PARAMETERS ARE NULL
               Response.Clear();
               Response.Write("REDIRECT=" + Request.Url.AbsoluteUri.Substring(0, pos + 1) + "PaymentError.aspx?Message=PARMETER VALIDATION FAILED");
               Response.End();
               }
               else
               {
               string ReqTranportalId = string.Empty;
               string ReqTranportalPassword = string.Empty;
              
               //DUAL VERIFIACTION URL, this is test environment URL, contact bank for production DUAL Verification URL
               string INQUrl = "https://" + PAYMENT GATE WAY URL(SECUREPG / SECUREPGTEST) + ".fssnet.co.in/pgway/servlet/TranPortalXMLServlet";
               ReqTranportalId = "<id>" + TRANSPORTAL ID PROVIDED BY BANK + "</id>";
               ReqTranportalPassword = "<password>" + TRANSPORTAL PASSWORD PROVIDED BY BANK + "</password>";
              
               // Pass DUAL VERIFICATION action code, always pass "8" for DUAL VERIFICATION
               string INQAction = "<action>8</action>";
               //Pass PG Transaction ID for Dual Verification
               string INQTransId = "<transid>" + ResTranId + "</transid>";
               //create string for request of input parameters
               string INQRequest = ReqTranportalId + ReqTranportalPassword + INQAction + INQTransId;
   
               try
               {
                   //create a SSL connection xmlhttp formated object server-to-server
                   System.IO.StreamWriter myWriter = null;
                   // it will open a http connection with provided url
                   System.Net.HttpWebRequest objRequest = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(INQUrl);//send data using objxmlhttp object
   
                   objRequest.Method = "POST";
                   objRequest.ContentLength = INQRequest.Length;
                   objRequest.ContentType = "application/x-www-form-urlencoded";//to set content type
                   myWriter = new System.IO.StreamWriter(objRequest.GetRequestStream());
   
                   myWriter.Write(INQRequest);//send data
                   myWriter.Close();//closed the myWriter object
   
                   System.Net.HttpWebResponse objResponse = (System.Net.HttpWebResponse)objRequest.GetResponse();
   
                   //receive the responce from objxmlhttp object
                   using (System.IO.StreamReader sr = new System.IO.StreamReader(objResponse.GetResponseStream()))
                   {
                   TranInqResponse = sr.ReadToEnd();
                   string[] INQCheck = GetStringInBetween(TranInqResponse, "<result>", "</result>", false, false);//This line will check if any error in TranInqResponse        
   
                   if (INQCheck[0] == "CAPTURED" || INQCheck[0] == "APPROVED" || INQCheck[0] == "SUCCESS")
                   {
                       string[] INQResResult = GetStringInBetween(TranInqResponse, "<result>", "</result>", false, false);//It will give DualInquiry Result
                       string[] INQResAmount = GetStringInBetween(TranInqResponse, "<amt>", "</amt>", false, false);//It will give Amount
                       string[] INQResTrackId = GetStringInBetween(TranInqResponse, "<trackid>", "</trackid>", false, false);//It will give TrackID ENROLLED
                       string[] INQResPayid = GetStringInBetween(TranInqResponse, "<payid>", "</payid>", false, false);//It will give payid
                       string[] INQResRef = GetStringInBetween(TranInqResponse, "<ref>", "</ref>", false, false);//It will give Ref.NO.
                       string[] INQResTranid = GetStringInBetween(TranInqResponse, "<tranid>", "</tranid>", false, false);//It will give tranid                                  
   
   
                       //UPDATE THE PAYMENT RESPONSE IN DB BASED ON PAYMENT STATUS   
                       //switch (INQCheck[0].Trim())
                       //{
                       //    case "CAPTURED":
                       //    break;
                       //    case "APPROVED":
                       //    break;
                       //    case "SUCCESS":
                       //    break;
                       //    default:
                       //    break;
                       //}
   
                       Response.Clear();
                      
                       //REDIRECT TO OTHER PAGE OR SHOW THE PAYMENT STATUS ON THE SAME PAGE
                       Response.Write("REDIRECT=" + strURL);
                       Response.End();           
                     
                   }
                   else
                   {
                       // PAYMENT NOT SUCCESSFUL
                       // REDIRECT TO ERROR PAGE              
                   }
                   }
               }
               catch (Exception ex)
               {
                   // REDIRECT TO ERROR PAGE IN CASE OF ANY ERROR
               }
               }
           }
           else
           {
               // REDIRECT TO ERROR PAGE IF PAYMENT IS NOT SUCCEEDED
           }
           }
           else
           {
           // REDIRECT TO ERROR PAGE IF THE ERROR MESSAGE IS NOT NULL
           }
       }
   
       #endregion
   
   }
   
   public static string[] GetStringInBetween(string strSource, string strBegin, string strEnd, bool includeBegin, bool includeEnd)
       {
           string[] result = { "", "" };
           int iIndexOfBegin = strSource.IndexOf(strBegin);
           if (iIndexOfBegin != -1)
           {
               // include the Begin string if desired
   
               if (includeBegin)
               {
                   iIndexOfBegin -= strBegin.Length;
               }
               strSource = strSource.Substring(iIndexOfBegin + strBegin.Length);
               int iEnd = strSource.IndexOf(strEnd);
               if (iEnd != -1)
               {  // include the End string if desired
                   if (includeEnd)
                   { iEnd += strEnd.Length; }
                   result[0] = strSource.Substring(0, iEnd);
                   // advance beyond this segment
                   if (iEnd + strEnd.Length < strSource.Length)
                   { result[1] = strSource.Substring(iEnd + strEnd.Length); }
               }
           }
           else
           // stay where we are
           { result[1] = strSource; }
           return result;
       }//String function end