"Undefined index" when quoting an array key

Question

I have a form in index.php

<?php 
  echo '<form action="update_act.php" method="POST">';
  echo '<input type="submit" name="'.$row['act_name'].'" value="edit">
  echo </form>
?>

Here $ row ['act_name'] is the value retrieved from the database.

My file update_act.php

<?php
   echo "Old Activity Name : ".$_POST['$row[\'act_name\']'];
?>

But I get an error message Undefined index: $row['act_name'] in C:\wamp\www\ps\activity\update_act.php.

I want to have different names for different submits, but I can not get its value on another page. Is there any way to do this?

Answer 1

PHP only replaces variables enclosed in double quotes" . Do you want to:

echo "Old Activity Name : ". $_POST[$row['act_name']]

---

But your whole form makes no sense. You'll get:

Old Activity Name : edit

because it is the value of the submit button.

Can you clarify your question, what do you want to achieve? Here are some thoughts on my part:

, :

<form action="update_act.php" method="POST">;
    <input type="hidden" name="act_name" value="<?php echo $row[act_name] ?>" />
    <input type="submit" name="submit" value="edit">
</form>

// ---- other file ---

<?php
   echo "Old Activity Name : ".$_POST['act_name'];
?>

---

?
? , , , , :

<form action="update_act.php" method="POST">;
    <input type="submit" name="submit" value="edit">
</form>

<form action="update_act.php" method="POST">;
    <input type="submit" name="submit" value="delete">
</form>

<?php 
if($_POST['submit'] == 'edit') {

}
else if ($_POST['submit'] == 'delete') {

}

Answer 2

, , $row ['act_name'] ( script), :

echo "Old Activity Name : ".$_POST[$row['act_name']];

Answer 3

Use $_POST[$row['act_name']].

Answer 4

   echo "Old Activity Name : ".$_POST['$row[\'act_name\']'];

it should be

   echo "Old Activity Name : ".$_POST["$row[act_name]"];

or

   echo "Old Activity Name : ".$_POST[$row[act_name]];