Get value from URL variable. PHP. The form uses POST method

Question

I would like to save the text from a textbox. I want to get the value of idForo in the URL.

http://localhost/foro1/indice.php?idForo=1

I get the error

Notice: Undefined index: idForo in C:\xampp\htdocs\foro1\indice.php on line 44

The controller

if (isset($_GET['newAnswer'])){
    $idForo=$_POST['idForo']; /*line 44*/
    $newAnswer=$_POST['newAnswer'];
    //Save new answer using PDO
    header("Location:indice.php?idForo=$idForo");

}

The form

<form method='post' action='indice.php'>
            <textarea rows='7' cols='60' name='newAnswer' required></textarea> <br>
            <input type='submit' class='responder' value='Responder' name='comentario'>
</form>

I appreciate your help

Answer 1

To get variables from the query string, you need to use $_GET . $_POST represents data that is sent to the script via the HTTP POST method.

You're also translating (?) the post variable name for the textarea for some reason?

Try:

if (isset($_POST['nuevaRespuesta'], $_GET['idForo'])) {
    $idForo = $_GET['idForo']; /*line 44*/
    $newAnswer = $_POST['nuevaRespuesta'];
    //Save new answer using PDO
    header("Location: indice.php?idForo=$idForo");
}

Answer 2

To get the value of a variable, you need to use $_GET

in your example, you just need to do this:

$idForo = $_GET['idForo'];

this will create a new variable $idForo from the variable in your URL. Hope this helps.

To get the variable into your form, you would need to change the first line to this:

<form method='post' action='indice.php?idForo=<?php $idForo ?>'>

Answer 3

idForo might not be in the $POST array, so use the following to allow for that scenario:

  if(isset($_GET['idForo'])) {
    $idForo = $_GET['idForo'];
  } else {
    $idForo = null;
  }