php - Edit button is undefined id of table -

i have code edit button:

<form method="post" action="pengiriman-input.php">     <input type="hidden" name="id" value="<?php echo $row['id_transaksi']; ?>" />     <input type="submit" value="kirim" /> </form> 

and in pengiriman-input.php

<?php  session_start();  $_session['id_transaksi'] = $_post['idtransaksi']; ?> 

but result is:

undefined index: idtransaksi in > c:\xampp\htdocs\delivery\pengiriman-input.php

how call value of $row['idtransaksi'] pengiriman-input.php?

$row['idtransaksi'] mysql query.

typo within post name within name attribute name='id' , not idtransaksi

$_session['id_transaksi'] = $_post['idtransaksi'];                                     ^^^^^^^^^^^ 

it should

$_session['id_transaksi'] = $_post['id'];                                     ^^^ 

or can check either using isset function of php

$_session['id_transaksi'] = (isset($_post['id'])) ? $_post['id'] : 0;