How to fill <select> with options using PHP and SQL? - php

Question

My question is: I want to show all SQL answers from a specific table inside the <select> using php.
I have tried to get it working, but without much success as it only shows one result.
<?php
error_reporting(E_ALL);
include 'connect.php';
include 'header.php';
set_time_limit(10);
$cat = $bdd->query('SELECT cat_id,cat_name,cat_description FROM categories');
$categories_list = $cat->fetch();
While ($categories_list = $cat->fetch()) {
$cat_name = $categories_list['cat_name'];
}
$cat->closeCursor();
echo '<form method="post" action="accès/create_topic_post.php">';
echo '<label for="sujet">Sujet :';
echo '<input type="text" name="sujet" id="sujet" required autofocus>';
echo '</label>';
echo '<label for="cat">Catégories :';
echo '<select name="topic_name">';
echo "<option value=\"".$cat_name."\" >$cat_name </option>";
echo '</select>';
echo '<input type="submit" value="Envoyer">';
echo '</form>';
?>

Answer 1

That's totally not the way to do it. Have a separation between PHP and HTML. And make sure you have the option echoed out inside the loop. Something like this:
<form method="post" action="accès/create_topic_post.php">
<label for="sujet">Sujet :
<input type="text" name="sujet" id="sujet" required autofocus>
</label>
<label for="cat">Catégories :
<select name="topic_name">
<?php
// Loop it here.
while ($categories_list = $cat->fetch()) {
$cat_name = $categories_list['cat_name'];
echo "<option value=\"".$cat_name."\" >$cat_name </option>";
}
?>
</select>
</label><!-- You forgot this -->
<input type="submit" value="Envoyer" />
</form>

Answer 2

There are two approach to achieve your desired output.
Approach One:
Store cat_name in a new array and use it in your HTML or anywhere, where you want to use.
<?php
$cat_name = array();
while($categories_list = $cat->fetch()) {
$cat_name[] = $categories_list['cat_name'];
}
?>
<select name="topic_name">
<?php
foreach ($cat_name as $key => $value) {
?>
<option value="<?=$value?>" ><?=$value?> </option>
}
?>
</select>
Approach 2:
<?php
while ($categories_list = $cat->fetch()) {
?>
<option value="<?=$categories_list['cat_name']?>" ><?=$categories_list['cat_name']?> </option>
<?php
}
?>
Whats wrong with your code:
$cat_name = $categories_list['cat_name']; this will only store the last value of your query, you must need to store the value in an array or use <option> inside the while() loop.

Answer 3

You keep replacing cat_name every time you read data from the SQL server. You need to store it in an array
<?php
error_reporting(E_ALL);
include 'connect.php';
include 'header.php';
set_time_limit(10);
$cat = $bdd->query('SELECT cat_id,cat_name,cat_description FROM categories');
//$categories_list = $cat->fetch(); This line discards a row of data
$cat_names = array(); //array for category names
While ($categories_list = $cat->fetch()) {
//Add newest 'cat_name' to the array
$cat_names[] = $categories_list['cat_name'];
}
$cat->closeCursor();
echo '<form method="post" action="accès/create_topic_post.php">';
echo '<label for="sujet">Sujet :';
echo '<input type="text" name="sujet" id="sujet" required autofocus>';
echo '</label>';
echo '<label for="cat">Catégories :';
echo '<select name="topic_name">';
//Loop and read back each category name
foreach ($cat_names as $cat_name){
echo "<option value=\"".$cat_name."\" >$cat_name </option>";
}
echo '</select>';
echo '<input type="submit" value="Envoyer">';
echo '</form>';
?>

Answer 4

You don't have to loop over results manually, as PDO has a function that can do it for you already, called fetchAll(). You have to use it instead of fetch() if you want to get an array of rows.
However, beside it, you need to learn PHP and programming in general. Because your current code makes little sense. To output an array, you have to use a loop:
$cat = $bdd->query('SELECT cat_name FROM categories');
$categories_list = $cat->fetchAll(PDO::FETCH_COLUMN); // here it is
echo '<form method="post" action="accès/create_topic_post.php">';
echo '<label for="sujet">Sujet :';
echo '<input type="text" name="sujet" id="sujet" required autofocus>';
echo '</label>';
echo '<label for="cat">Catégories :';
echo '<select name="topic_name">';
foreach ($categories_list as $cat_name)
{
echo "<option value='$cat_name'>$cat_name</option>";
}
echo '</select>';
echo '<input type="submit" value="Envoyer">';
echo '</form>';

Answer 5

Move the fetch loop to the output section of your code.
So instead of this:
echo "<option value=\"".$cat_name."\" >$cat_name </option>";
move the loop so it will look like this:
While ($categories_list = $cat->fetch()) {
$cat_name = $categories_list['cat_name'];
echo "<option value=\"".$cat_name."\" >$cat_name </option>";
}

Answer 6

Use while loop while you're outputting the category in select option.
Like this,
While ($categories_list = $cat->fetch()) {
echo "<option value=\"".$categories_list['cat_name']."\" >$categories_list['cat_name'] </option>";
}