How to set the value associated with an <a> link as a session variable, when clicked

Question

I have seen examples for this online, but it only seems to break my code. I want to be able to I would like to store a field queried, using the code below in a session variable.

PHP:

<?php

// Collect input
// If an input has been given
if(isset($_POST["aSearch"])) {
  $searchq = $_POST["aSearch"];
  $searchq = preg_replace("#[^0-9a-z]#i","",$searchq); //Can only search words

// Select records if name's match
$sql = "SELECT * FROM birdt WHERE birdName LIKE '%$searchq%'";
}

// Tests if connection is made to the db to query it
if ($conn->query($sql)=== TRUE){
  echo "The rows you have searched for are:";
} else {
  echo "Connection failed: ";
  echo $conn->error;
}

// Show fields
$result = $conn->query($sql);

// Output data of each row
if ($result-> num_rows> 0) {
  readfile("ViewReturn.html");
  while($row = $result-> fetch_assoc()) {
    // redirect the user to a new page
    echo "<a href='sort.php'> Bird Name: ".$row["birdName"]. "</a><br><br>"; // Important row 
  }
} else {
  echo "0 results";
}

?>

This code can be used to return values from the database depending on the users input. It will return the "birdName" and allow the user to click a queried result to go to the "sort.php" page.

How would you store the returned field "birdName" once/before it's clicked in a session variable, so it can be accessed in the following page?

PS I understand my question is quite specific and unideal, but I'm seriously struggling to get this to work, and I'm quite desperate, thanks.

Answer 1

At the beginning of the script you need to put

session_start();

Then you can save all the bird names in an array in a session variable, by pushing each bird name from the database onto this array.

$_SESSION['birdNames'] = array();

if ($result-> num_rows> 0) {
  readfile("ViewReturn.html");
  while($row = $result-> fetch_assoc()) {
    // redirect the user to a new page
    $_SESSION['birdNames'][] = $row['birdName'];
    echo "<a href='sort.php'> Bird Name: ".$row["birdName"]. "</a><br><br>"; // Important row 
  }
} else {
  echo "0 results";
}

sort.php can then use session_start(); to continue the session, and access $_SESSION['birdNames'] to get all the bird names.

However, I suspect this isn't really what you want. If you want sort.php to just process the specific bird name that the user clicked on, you shouldn't use a session variable, it should be a URL parameter.

echo "<a href='sort.php?id=" . $row["id"] . "'> Bird Name: ".$row["birdName"]. "</a><br><br>";

Then sort.php can use $_GET['id'] to get the ID of the bird that the user clicked on.