PHP从循环中获取每个对象的id并使用另一个页面

Question

I have a code that retrieves data from database. I need to show detailed information of clicked object on another page according to the id of the object. How can I achieve this? When I set $_SESSION and use in another page it takes only last value. Codes retrieves info is as following.

<?php
include("misc.inc");
session_start();
$connect = mysqli_connect($host,$user,$password,$database) or die ("Couldn't connect database");
$sql    =   "SELECT * FROM ad ORDER BY training_start desc";
$result =   mysqli_query($connect,$sql) or die("Couldn't execute query.");
echo    "<table cols='4'  cellspacing='25'>";
echo    "<th>ID</th>";
echo    "<th>Training Name</th>";
echo    "<th>Trainer Name</th>";
echo    "<th>Training Dates</th>";
echo    "<th>Registration Starts</th>";

while($row=mysqli_fetch_assoc($result))
{

extract($row );


echo    "<tr><td >$id</td>";
echo    "<td  ><a href='ad_details.php'>$training_name</a></td>";
echo    "<td >$trainer_name</td>";
echo    "<td >$training_start - $training_end</td>";
echo    "<td >$reg_start</td></tr>";

}

echo    "</table>";

?>

Answer 1

You need to change this line :

echo    "<td  ><a href='ad_details.php'>$training_name</a></td>";

To :

echo    "<td  ><a href='ad_details.php?id=$id'>$training_name</a></td>";

Then on details.php use get method to get the id

if(isset($_GET['id']) && !empty($_GET['id'])){

 $currentID = $_GET['id'];

 // Then select what you want where id = $currentID


}else{

    //id not set redirect back / return error
}

Side Note : if you are not using prepared statements I strongly advice that you start using them.