pgResponse.php

<?php
header("Pragma: no-cache");
header("Cache-Control: no-cache");
header("Expires: 0");

// following files need to be included
include_once("lib/config_paytm.php");
include_once("lib/encdec_paytm.php");

$paytmChecksum = "";
$paramList = array();
$isValidChecksum = "FALSE";

$paramList = $_POST;
$paytmChecksum = isset($_POST["CHECKSUMHASH"]) ? $_POST["CHECKSUMHASH"] : ""; //Sent by Paytm pg

//Verify all parameters received from Paytm pg to your application. Like MID received from paytm pg is same as your application�s MID, TXN_AMOUNT and ORDER_ID are same as what was sent by you to Paytm PG for initiating transaction etc.
$isValidChecksum = verifychecksum_e($paramList, PAYTM_MERCHANT_KEY, $paytmChecksum); //will return TRUE or FALSE string.

if($isValidChecksum == "TRUE") {
	//Checksum matched and following are the transaction details:
	if ($_POST["STATUS"] == "TXN_SUCCESS") {
		//echo "Transaction status is Success";
		//Process your transaction here as success transaction.
		//Verify amount & order id received from Payment gateway with your application's order id and amount.
	}
	else {
		//echo "Transaction status is failure";
	}
/*
	if (isset($_POST) && count($_POST)>0 )
	{ 
		foreach($_POST as $paramName => $paramValue) {
				echo "Please Wait ...";
				echo "<br/>" . $paramName . " = " . $paramValue;
		}
	}
*/	
}
else {
	//Process transaction as suspicious.
}

?>
<header>
    <link href="https://fonts.googleapis.com/css?family=Roboto|Varela+Round" rel="stylesheet">
    <link rel="stylesheet" href="https://fonts.googleapis.com/icon?family=Material+Icons">
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css">
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css"
        integrity="sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" crossorigin="anonymous">
</header>
<h1 class="text-center">Please Wait ....<h1>
        <div class="d-flex justify-content-center">
            <i class="fa fa-spinner fa-pulse fa-3x fa-fw text-center"></i>
        </div>
        <form method="post" action="status.php" name="f1">
            <table style="border: 1px solid black;">
                <tbody>
                    <?php
					foreach($_POST as $paramName =>  $paramValue) { 
						?>
                    <input type="hidden" name="<?php echo $paramName ?>" id="<?php echo $paramName ?>"
                        value="<?php echo $paramValue ?>">
                    <?php
					}
					?>
                    <?php
					if(!isset($_POST['TXNDATE']) && !isset($_POST['GATEWAYNAME'])){ ?>
                    <input type="hidden" name="TXNID" id="TXNID" value="NAN">
                    <input type="hidden" name="PAYMENTMODE" id="PAYMENTMODE" value="NAN">
                    <input type="hidden" name="TXNDATE" id="TXNDATE" value="NAN">
                    <input type="hidden" name="GATEWAYNAME" id="GATEWAYNAME" value="NAN">
                    <input type="hidden" name="BANKTXNID" id="BANKTXNID" value="NAN">
                    <?php
					}
					?>
                    <input type="hidden" name="NAME" id="NAME" value="<?php echo $_COOKIE['NAME']?>">
                    <input type="hidden" name="CUST_ID" id="CUST_ID" value="<?php echo $_COOKIE['CUST_ID']?>">
                    <input type="hidden" name="EMAIL_ID" id="EMAIL_ID" value="<?php echo $_COOKIE['EMAIL_ID']?>">
                    <input type="hidden" name="Anonymous" id="Anonymous" value="<?php echo $_COOKIE['Anonymous']?>">

                </tbody>
            </table>
            <script type="text/javascript">
            setTimeout(() => {
                document.f1.submit()
            }, 1500);
            </script>
            <!-- jQuery first, then Popper.js, then Bootstrap JS -->
            <script src="https://code.jquery.com/jquery-3.3.1.min.js"
                integrity="sha256-FgpCb/KJQlLNfOu91ta32o/NMZxltwRo8QtmkMRdAu8=" crossorigin="anonymous"></script>
            <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js"
                integrity="sha384-ZMP7rVo3mIykV+2+9J3UJ46jBk0WLaUAdn689aCwoqbBJiSnjAK/l8WvCWPIPm49"
                crossorigin="anonymous"></script>
            <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js"
                integrity="sha384-ChfqqxuZUCnJSK3+MXmPNIyE6ZbWh2IMqE241rYiqJxyMiZ6OW/JmZQ5stwEULTy"
                crossorigin="anonymous"></script>
        </form>