php变量的输入值

Question

I am a beginner and I am trying to integrate Paypal into my website. In my cart there is a table which displays the total amount:

<td class="total_amount"><b>'.$_POST['amount'].'</b></td>

Now, I want to retrieve this amount and send it to paypal:

<form action="paypal_ec_redirect.php" method="post">
<input type="hidden" name="PAYMENTREQUEST_0_AMT" value="'.$_GET['amount'].'"></input>

This doesn't work and am having errors:

SetExpressCheckout API call failed. Detailed Error Message: Order total is missing.Short Error Message: Transaction refused because of an invalid argument. See additional error messages for details.Error Code: 10400Error Severity Code: Error

Help please.

Answer 1

try this

<td class="total_amount"><b> <?=$_POST['amount'] ?></b></td>

and

<form action="paypal_ec_redirect.php" method="post"> <input type="hidden" name="PAYMENTREQUEST_0_AMT" value=" <?=$_POST['amount'] ?>"></input>